When my car was stolen (my brand new car!) at the beginning of this year, I started to seriously think about getting an alarm installed. (Who would've thought a MINI-VAN would be stolen?!)
When I got my car back--luckily in one piece--I immediately made an appointment with Jimmy. It must have been a pain to install an after-market alarm on my car because it took most of the morning, but there were no complaints from Jimmy. He didn't even charge me extra--what he quoted me the day before is what I paid.
He also works out of local dealerships like Cadillac, so if they trust him, you know you can too.