I had an issue with my Canon 20d and took it to Camera Repair Center. The guy told me what he thought was wrong and gave me an idea of what to expect. A week later he called to verify the problem and ok the repair charges with me. It wasn't real cheap but I think he was fair and did a good repair on it he even got that pesky spot out of the viewfinder. It's been going strong now for 4 months.
Pros: Friendly service and was accurate in assessment of trouble
Cons: Not located near to me.