Lexus Rz vs MG Im5

What's the difference?

Smooth, quiet, quality sums up this new and improved Lexus RZ. But will tricky new tech like steer-by-wire and a manual mode in the F Sport's auto transmission be enough to sway more premium electric SUV buyers its way? Fold in this car’s value proposition as well as the brand’s spectacular ownership package and it just might be.

Note: CarsGuide attended this event as a guest of the manufacturer, with travel, accommodation and meals provided.

The MG IM5 Performance is fast, comfortable, quiet and super refined. Putting some minor spec and active safety niggles to one side, it offers the features, tech and price to match it with its well-credentialled and already popular mid-size EV sedan competitors. Is there room for one more? We think there should be.

Not a tremendous amount of change in terms of exterior design for this update with the brand’s signature angular treatment retained including a prominent snub nose and 20-inch rims on both variants of the car.

The top-spec F Sport picks up extra aero-focused elements, particularly around the lower bumper at the front, as well as aero covers on the wheels and at the back a spoiler on the tailgate as well as a faux diffuser at the bottom of the lower bumper.

Not much has changed inside either except for a steering wheel-shaped elephant in the room in the form of a yoke that goes with the steer-by-wire function on the 550e F Sport. A significant, eyebrow-raising departure.

However, the curved instrument binnacle, central 14-inch multimedia screen as well as the design of the centre console remain unchanged. 

Having said that, there are new ‘laser-patterned’ designs in the door card trims and dynamic lighting graphics in the doors, as well.

The functionality of the touch-dimmable panoramic roof has also been improved and it works beautifully.

Playing spot the straight line on the outside of the MG IM5 is like an automotive design version of Where’s Wally? There aren’t many, in the midst of an unrelentingly curvaceous exterior treatment.

At close to five metres long and two metres wide the IM5 is appreciably longer (+211mm), a little wider (+27mm) and a bit taller (+33mm) than a Tesla Model 3. Think BMW 5 Series in terms of overall size.

And the soft-form shape is functional; the swoopy liftback boasting an ultra-slick 0.24 drag coefficient.

That said, I’m not convinced by the ‘Periscopic’ cameras informing the driver assistance systems from the front guards. They scream tacked-on afterthought. But a touch-only initial opening function for the flush door handles is cool and makes life easier.

The curves continue inside with soft-padded surfaces around the dash and doors, but the straight edge obviously came out for the 10.5-inch central media screen and vast 26.3-inch upper display. There are next to no buttons; even exterior mirror adjustment is directed from the screen to a multi-function steering wheel control.

System software (powered by a Qualcomm ‘Snapdragon’ chip) is lightning fast with a two-finger up and down swipe shortcut function on the central screen for ventilation and other functions.

The interior is light and bright thanks to the enormous panoramic sunroof. It’s been fine in cooler winter conditions during this test but it could be interesting to revisit in the heat of an Aussie summer

There are two interior colour schemes available - the ‘Highland Grey’ of our test car or ‘Dover Beige’ for those brave enough to live life with the threat of scuff marks on your shiny new car’s glamorous but vulnerably light interior.

At a fraction over 4.8m long, close to 1.9m wide and a bit more than 1.6m tall, with a 2850mm wheelbase, the ZR is a sizeable machine. 

There’s plenty of breathing space in the front and in terms of practicality the first thing that jumps out, or rather it doesn’t, is the lack of a conventional glove box.

But there is a large box between the front seats to take its place, with the lid (which doubles as a centre armrest) performing the Lexus party trick of being able to open towards the driver or passenger.

There are two cupholders in the centre console with a wireless charging pad ahead of them, plus decent bins in the doors for bottles and other bits and pieces. An additional tray sits under the main, flying buttress-style upper console.

For power and connectivity, there are USB-C sockets for charging and media as well as a 12-volt socket in the lower console section.

Getting into the back is easy thanks to wide-opening doors and a large entry aperture and seated behind the driver’s seat set for my 183cm position I’ve got hectares of leg- and headroom. Shoulder room is best for two full-size adults rather than three, which would be a short-journey squeeze. Three up to mid-teenage kids will be fine.

In terms of storage there are pockets on the front seatbacks, bins able to hold a large bottle in the doors and two cupholders in the fold-down centre armrest. Individual ventilation control for rear seat passengers is always welcome. 

Then for power, there are two USB-C outlets and a ‘house-power’ socket underneath them. The 550e F Sport also includes heating controls for the two outer rear positions.

Lower rear axle packaging enhances boot space with a generous 522 litres on offer, expanding to 1451L with the 60/40 split-folding second row lowered. Tie-down anchors and bag hooks are a thoughtful touch and there are handy storage boxes under the flat floor, ideal for charging cables. 

The standard power tailgate is nice, while a repair-inflator kit instead of a proper spare isn’t. Braked trailer towing capacity is a handy 1.5 tonnes.

There’s plenty of breathing room up front and in terms of storage one of the first things worth calling out are the long but relatively narrow door bins. No good for anything above unusually slender bottles, even if they’re lying down.

No conventional glove box in the dash, but there is a large lidded box (cooled and heated) between the seats that doubles as a centre armrest. It’s supplemented by a big stowage area underneath the flying buttress style centre console.  

There are two cupholders in the centre console as well as a wireless device charging pad in front of them with a vaguely phone-shaped oddments bin alongside it.  

Move to the rear and the IM5’s 75mm wheelbase advantage over the Tesla Model 3 is clear. Heaps of knee and headroom for me at 183cm sitting behind the driver’s seat set to my position. 

But… the seat sits low which pushes your knees up into the air to the point where my thighs are not contacting the seat cushion. Even though the rear seat reclines to a certain degree it’s a problem compounded by a chronic lack of room for your toes under the front seat. Awkward.

There are map pockets in the front seatbacks, modest bins in the doors and a fold-down centre armrest with two cupholders. Adjustable ventilation in the rear of the front centre console always makes life in the rear seat more pleasant.

The car also houses ‘Strong Magnets’ at various points around the cabin and boot, with a configurable adapter able to lock a phone or tablet into place for the entertainment of, in our case, back seaters. 

Speaking of devices for entertainment, there are two USB-C sockets and a 12-volt outlet in the front and another USB-C and 12V in the back, so charging isn’t an issue. 

The IM5 is a liftback so the boot aperture is generous and a capacity of 457 litres with the rear seats up is decent for a car of this size, although that’s less than the Tesla Model 3 (594L) which has an additional well under the floor. 

Still, enough room for the largest (124L) and smallest (36L) suitcases from the CarsGuide three-piece luggage set with some room to spare.

The power tailgate can be operated hands-free via the key or an always welcome under bumper kick function.

Volume expands to 1290 litres with the rear seats folded and there’s a modest 18-litre ‘frunk’ under the bonnet.

The bad news is a repair-inflator kit rather than a physical spare wheel, but the better news is the IM5 Performance can tow a 1500kg braked trailer (750kg unbraked).

The IM range also features the ‘MG iSmart’ app allowing remote control of various functions including charging, checking vehicle location and route planning. 

At $80,990, drive-away, the IM5 Performance sits at the top of a three-grade line-up that starts with a 75kWh RWD Premium model at $60,990, followed by a mid-spec 100kWh RWD Platinum for $69,990, both drive-away.

Its most prominent competitor is arguably the Tesla Model 3 Dual Motor AWD ($80,900), with others including the BYD Seal Performance AWD ($68,798), Hyundai Ioniq 6 AWD Epiq ($86,500) and Polestar 2 Long Range Dual Motor Performance ($80,380).

Worth noting, too, the IM6 range - essentially the same car with a taller SUV body - has the same model walk-up and identical pricing.

Once you’ve crossed the $80K threshold it’s fair to expect a decent basket of standard fruit and aside from the dynamic and safety features we’ll get to shortly, the IM5 Performance comes to the party.

Highlights include a double-glazed panoramic roof, power-adjustable (12-way driver, six-way passenger) heated and ventilated front seats (also heated in the rear), dual-zone climate control, 20-speaker audio (with digital radio), 256 colour ambient lighting, a power tailgate (with hands-free function) and 20-inch alloy rims.

There’s also adaptive cruise control, a heated steering wheel, wireless Android Auto and Apple CarPlay, LED headlights, keyless entry and start, wireless device charging (50W), a 10.5-inch central control screen and a sweeping 26.3-inch upper screen; the right side for instrumentation and car data, the (touch-sensitive) left side for multimedia and other onboard functions.

There’s more and it’s clear this car at least matches or betters its direct competitors for included equipment.

Both versions of the new RZ are powered by dual permanent magnet synchronous motors, one in the front, one at the back, each producing 167kW and 269Nm. 

Total output is 280kW for the 500e (up from 230kW in the 450e), with a little more juice released from the motor combination for the 550e at 300kW.

A single-speed transmission sends drive to both axles and the RZ550e F Sport features ‘Interactive Manual Drive’ designed to give the sensation of manual gear shifts in a BEV. More on that in the Driving section.

The MG IM5 Performance is powered by an electric motor on each axle - the rear (372kW/500Nm) more powerful than the front (200kW/300Nm), for overall outputs of 572kW (that’s close to 770hp) and 802Nm of pulling power.

The official term for that amount of grunt is… a lot. And we’ll get to what it means on the road in the Driving section shortly.

The RZ500e and 550e are fitted with a 77kWh lithium-ion battery delivering a claimed (WLTP) range of 450 and 456km, respectively.

Claimed 10-80 per cent charge time, using its full 150kW DC fast-charge capacity, is 30 minutes or a handy three and half hours at maximum 22kW AC capacity.

Energy consumption on the combined (urban/extra-urban) cycle is 18.2kWh/100km (WLTP) for the RZ500e and 18.4 for the 550e.

Over several hundred kilometres of B-road and freeway running as well as pottering through slow-speed villages on the launch we saw an average of 19.3kWh/100km in the 500e and 20.1 in the 550e F Sport, which is pretty handy.

And the (very) good news is two AC charging cables, installation of a home charger and three years’ complimentary charging across the Chargefox network is included. Nice!

The MG IM5 Performance features an 800-volt electrical architecture which means the 100kWh NCM battery can accept a DC peak charge of close to 400kW.

Only snag is the highest you’ll currently find in Australia is 350kW. But even at that rate you’ll still be looking at a 30-80 per cent charge in just over 15 minutes. Maximum AC charge rate is 11kW.

Claimed range is 575km (WLTP) which is less than the Tesla Model 3 Dual Motor AWD at 629km.

Over a week of city, suburban and some freeway running we saw average energy use of 20.6kWh/100km which is on the high side for an EV of this size but maybe not for one with this kind of performance potential. 

It’s a hefty machine at 2.1 tonnes, but Lexus says the RZ550e F Sport will accelerate from 0-100km/h in 4.4 seconds, with the 500e only marginally slower at 4.6sec.

In straight-line acceleration Lexus says front to rear power distribution varies between 60:40 to 100 per cent rear to suppress pitching and “produce a more direct acceleration feel”. 

And the RZ is indeed quick. Apply your right foot at just about any speed and the car rockets ahead with satisfying enthusiasm.

The F Sport’s ‘manual’ mode allows you to shift through eight virtual ‘ratios’. Press the ‘M’ button on the console and bingo, you have slim steering wheel-mounted paddles to control them.

At anything above a light accelerator application you’ll feel a jolt on upshifts, but it’s rather unpleasant. Sure, you want some sense of a gear change, but you feel it in your core. Check out the video review to see how much it can shake you around. 

A synthetic soundtrack Lexus refers to as the “BEV Sound”, vaguely echoing an internal combustion engine, is fed through the F- Sport’s audio system and it feels thin and brittle to our ears. Again, check out the audio sample in our video review to see if you agree.

You’ll hear the ‘revs’ rising on up and downshifts but there’s no physical accompaniment with the latter as far as we could sense.

Suspension is strut front with double wishbones at the rear and it’s been given a thorough revision in terms of dampers, springs and bushings in both the 500e and 550e F Sport, with the latter copping some additional fine-tuning in each of those areas.

We sampled 500e and 550e F Sport versions of the RZ on the launch drive in Southern Portugal, covering mostly Aussie-compliant roads with lots of bumps and ruts to deal with. And despite its hefty kerb weight the car copes with these imperfections well.

There’s also been some extra attention paid to body rigidity in this updated RZ, specifically reinforcement of upper sections of the nose and around the boot to keep the car more torsionally stiff.

In cornering the drive distribution ratio is between 80:20 front to rear to RWD-only, according to vehicle speed and steering angle, and the car feels composed and predictable.

The F Sport features the steer-by-wire system, using a yoke rather than a conventional steering wheel and the ratio is such that all you have to do is turn the wheel slightly to generate a response.

It’s smooth and progressive but quick at the same time. You soon become used to it.

While it's unusual to see a small yoke in your hands rather than a steering wheel, it means you have an uninterrupted view through to the instruments, which is a nice side benefit.

However, much like the Infiniti Q50’s system before it, there is no mechanical link between the driver’s hands and front wheels. Steering inputs are relayed by electric signals from a torque actuator to a control actuator.

So, while Lexus says “important feedback filters through without the unpleasant vibration effects of a mechanical connection”, and that’s true, by definition there is no road feel and the wheel feels numb from that point-of-view. Worth noting the mechanically steered 500e feels much the same.

Tyres are Dunlop SP Sport Maxx (235/50 fr - 255/45 rr) which grip hard and remain relatively comfy despite their short sidewall running on 20-inch rims.

One price you pay for the steer-by-wire system’s set-up is a substantial turning circle, so be ready for that.

Braking is by ventilated discs all around, which work nicely, and when you’re not using the manual mode in F Sport the steering wheel paddles allow movement through four levels of regenerative braking.

The most aggressive setting will slow you quite markedly but not to the level of ‘single-pedal’ operation.

Additional sound insulation includes an under-seat rear floor silencer, soundproofing in the door trims as well liberal use of damping sheets, foam, silencer pads, insulators and extra seals. And the car is super-quiet, even for an EV.

In terms of miscellaneous observations, the front seats on both versions remained comfortable and supportive over long stints behind the wheel (and yoke!).

Slow speed manoeuvring is assisted by a 360-degree overhead camera view with a translucent trace of the car in the centre, as well as a high-quality reversing camera. Vision across the car and through to the back is good, anyway, but the extra tech helps in the slow speed stuff. 

There’s also a sensible mix of physical dials and on-screen controls and the touchscreen menus are easy to use. Especially handy when you’re racing to the function that turns off the intensely annoying over-speed warning.

First things first, the IM5 Performance is supercar fast. This 2.3-tonne five-seater blazes from 0-100km/h 3.2 seconds and with its dual motors combining to produce 572kW/802Nm, eye-widening performance always resides underneath your right foot.

But it’s not all about straight line speed. Ride comfort is excellent. Underpinned by an all-new platform, the IM5’s suspension is by double wishbones at the front and multi-links at the rear. But the key to its bump and rut smoothing ability is air suspension and ‘continuous control’ active damping.

Fold in double-glazing on the full-length glass roof and side windows, as well as active noise cancellation and you have a serene interior environment at any speed. Also worth noting the front seats are great; as grippy as they are comfortable.

Not only that, despite its relative heft, this mid-sizer steers well, too. Not the last word in road feel but it points accurately and the standard rear steering helps with prompt (but never jerky) cornering turn-in. Flick to ‘Sport’ mode and the IM5 is up for some enthusiastic running.

The rear wheels can turn up to 12 degrees in the opposite direction to the fronts at slow speed, which makes for a usefully tight 10-metre turning circle. But above that, at lesser angles, it adds extra stability and decisiveness in the way the car steers through even tight, twisty sections.

Rubber is top-shelf Pirelli P Zeros on 20-inch alloys (245/40 fr - 275/35 rr) and it grips hard, especially in the wet weather over much of the test period. Braking is solid, as it needs to be, with ventilated discs all around and four-piston callipers at the front. 

No adjustable regen braking but you can feel the ‘Cooperative Regenerative Brake System’ (CRBS) doing its thing when you lift off the accelerator. 

The physical rear view is modest thanks to the slope of the back window reducing its functional area for the driver to that of a 1950s VW Beetle. Even the interior rear-view mirror is tiny and folds up into a recess in the headliner if you’d prefer life without it.

But that’s where a rear camera view popping up on the upper screen display (accessed via the right-hand steering wheel click control) comes in handy. Side camera views are also available as is a 360-degree overhead view, which makes parking straightforward.

If you need more parking help there are various self-parking modes including a nifty ‘Curbside’ function that will realign the car hands-free if you’re parallel parked too far out from the kerb.

In a similar vein, a ‘Rainy Night’ mode projects left and right rear views onto the main screen using AI to enhance clarity and highlight pedestrians and cars.

Overall the ADAS (Advanced Driver Assistance Systems) are relatively unobtrusive but we found ourselves switching off the incessant overspeed chime that sounds for 10 seconds if you creep over the indicated speed limit, even when the system has misfired on the correct speed. For example, 40km/h school zones on a Sunday.

The over-zealous driver distraction warning also occasionally issued a visual and audible slap on the wrist when I was looking straight ahead. Tellingly, there’s a specific quick screen for turning both these functions off, but it kinda defeats the purpose of having them in the first place.

We also found the adaptive cruise control to be hesitant in multi-lane environments, reducing speed occasionally because the system seemingly believed a car was set to merge, when it wasn’t.

No independent ANCAP safety assessment at this point but there’s a full suite of active safety tech onboard including AEB, lane departure warning, blind spot detection, rear cross-traffic alert & braking, forward collision warning, lane-change assist, tyre pressure monitoring and heaps more. And we touch on how it all operates in the Driving section above.

There are no less than nine HD cameras, 12 ultrasonic sensors and three millimetre-wave radars on duty.

If a crash is unavoidable there are seven airbags including full-length side curtains and a front centre bag. Multi-collision brake also minimises the chances of subsequent impacts after an initial crash. There are also three top tether points and three ISOFIX child seats anchors across the second row.

All right on the pace for this part of the market and the IM5’s competitive set.

The RZ is covered by Lexus Australia’s five-year/unlimited km warranty and there’s an eight-year/160,000km warranty on the drive battery, which is in line with the RZ’s key competitors.

Recommended maintenance interval is 12 months/15,000km, which is relatively brief for an EV. 

Capped-price servicing is yet to be confirmed, but for reference the outgoing 450e runs to $395 for each workshop visit up to a maximum of five years/75,000km. That’s sharp pricing in this part of the market.

The RZ also qualifies its owner for ‘Platinum Electrified’ benefits under the ‘Lexus Encore’ ownership program. That means everything from access to “exclusive offers and events” to a complimentary service loan car, five years’ roadside assistance, valet parking at selected locations, airport lounge access and (heaps) more, including the charging benefits mentioned earlier. Hard to argue with that.

The MG IM5 Performance is covered by a seven-year/unlimited km warranty, which is a plus, but the catch is it’s conditional on authorised dealer servicing. Go elsewhere and the term drops to a more common five years/unlimited km. The drive battery is covered for eight years/160,000km, which is the norm in the Aussie market

Servicing is required every 12 months or 20,000km with charges averaging $586 per workshop visit for the first five years, which is on the high side for an EV, even at this price point, the average bumped up by a more than $1400 doozy at year four.

MG IM models are sold (with service available) through all of MG’s 100-plus dealerships across the country, so no concerns there.