I had to take my car in to them 4 times for the same problem. If it was a really hard problem that might be ok, but they didn't solve the problem systematically and seemed to be mostly interested in fixing SOMETHING so they could get my money.
The problem was a strong vibration when going 60 mph on the freeway. I told them this, but I later found out that they NEVER took the car on the freeway to check it-- neither before doing a repair, nor afterwards to see if it was fixed. Meanwhile they were telling me it was the left CV joint, then when that didn't work, it was the spark plugs, then it was the right CV joint, then it was that a tire was out of balance (a really cheap, easy fix). Meanwhile they charge for parts and labor all along with way.
It was infuriating. Maybe other Greg's locations are better. Don't go to this one.