I had a bad experience here but it seemed to be a rare case. First, I was promised a 2 week period for my car to be fixed ($6000 of Body work). Every time I called Mason for an update, I was told there was some new issue and was promised that the remaining additional parts would be in "the beginning of next week." After having to call at least three times a week every week, I got my car back about 6 weeks later. When I received my car, the body work looked great. Upon pulling out of the parking lot, two hard plastic cover pieces fell down on the underside of the front of the car and on the passenger inside floorboard. I turned around and asked for a new part since it was still broken. Instead of ordering a new part, he just used some hot glue to try to put it back together. Long story short, it kept falling out and I went back twice for him to fix it properly and he never did. As far as the extensive body work, everything was great!
Update: after posting my review, Mason personally contacted me to make this right and offered to do whatever it took to be certain that I was satisfied. Since I had recently moved across the country, he ordered me the part I needed and mailed it to me with a personal apology letter. The repairs are lifetime guaranteed as long as you own the car! Thanks Mason.