I have used Don's DI for years, for major issues: Air conditioning compressor, and a number of other at least quasi-high ticket repairs. It's extraordinary: There are cars all over the place and they're working all the time, so be ready to leave your vehicle there overnight for any big repair.
That said, in my view, they're the best mechanics in town with long-term experience and they stand behind their work. Have I had to bring my car back on a repair they did? Yes, at least once, maybe twice. But who hasn't?
Aside from getting the job done, pricing is the most important thing: Again, as an example, the air conditioning issue was literally less than half of anywhere I checked in town, and other repairs were equally low in price. (Nat B., while I don't mind disagreeing with people on restaurants, mechanics are different and I really do trust these guys. It was, by the August 2010 that I had the air issue in my car).
At the end of the day, why would I drive from Summerlin to Don's (I abhor driving anywhere), have to have someone follow me and take me back, if they weren't this good. I don't even like driving to restaurants I like -- I let my wife do it...It's the New Yorker in me.