Mitsubishi Pajero Sport 2016: Servicing and warranty

Last time I dropped you a line we were thinking about buying a Mitsubishi Challenger. Luckily you talked us out of it and we selected a new Pajero Sport Exceed instead and it is a great car. But I've a question about warranty terms. Over the years I have had all of my new cars serviced while under warranty by the dealer, so if there were a claim there would be no issues. Once out of warranty I've gone to our family mechanic who is a good operator. With the Pajero the first service at 15,000km was part of the purchase price and completed by Mitsubishi. But I have just had the 30,000 service completed by our family mechanic instead of Mitsubishi — $230 against $800 — and he has stamped the book and assures me my warranty is secure as he is registered to do the work. Do you think I am OK with this procedure or is it going to be a problem if there ever was a warranty claim?