I've done business with Tekserve for six years now, and my bank has all its Macs fixed here. I've dealt with Apple directly, and with a large commercial tech services firm that my bank uses for the PCs.
Nothing compares to the quality of the work and the knowledgeability of the staff at Tekserve. These people live and breath Mac, and it shows. They saved me over $1,800 in quoted repairs from another source and had my MacBook back to me in 24 hours last month. They explained the problem in detail, took their time, and knew what they were talking about.
Every place as big and busy as this is going to have some sad (and bad) stories to tell, and I think they should pay attention to the stories and improve any problems, but if you look around the Internet you'll quickly find that this place is THE PLACE when it comes to Macintosh service. They're the best, in my experience, and been that way for a couple of decades i think.
People with problems post more than people who had great experiences. I hope this helps provide a realistic balance to some of the (understandable) complaints up here.
Pros: Amazingly good service and deep Mac knowledge
Cons: Some of the most painful looking tattoos and piercings I've ever seen.
more