That's a good question, which I can't answer at the moment. I suspect it won't be a lot more for the extra money. What was interesting though, was that when I asked the question of the cheaper dealer he quoted me £135 at first, but then realised he had not included labour, which then pushed the price up to £235. So what bits does £135 buy. I can't imagine!!! Also how much time does £100 buy. A rip off probably, but I'm reluctant to move to an independent garage until the warranty has expired.