Competent, honest service.
Even though CompUSA across the street was much bigger, I got far better service from PTC at a lower price. Now CompUSA is gone, and they are not! Parts can be expensive, since they're too small to order in volume. But they do have some good deals on computers.
They have solved several problems hardware and software problems for me over the years. Once when I had a major disk crash, they were able to recover the entire contents, which meant a lot to me. They're also very good at resolving malware infections.