I've been taking several cars in the family to Roman at AutoCube. He's on Victoria St, about 5 minutes west of BMW Grand River. He is very passionate and knowledgable, works on everything from Mini's to M-cars, and will take the time to get it right. Very competitive rates too.
The only downside is that he's crazy busy most of the time. You have to call and book an appointment in advance. Sometimes that isn't convenient for oil changes or tire swaps, etc. Nevertheless, give him a call if you have a more complicated issue. He loves to chat, and often times will keep you on the phone for quite a while!