Hey I don't know much about the Mach 1 Kit. MAybe someone else does. But I put the bullitt suspension in beggning of the summer and i love it, less body roll and a tighter feeling. the car does ride harder though, and if u have anything heavy in the trunk or people in the back seat, the rear really takes the bumps hard. I did put new swaybar end links in, cause the stock ones go bad pretty fast and i put urethane bushings on instead of the rubber ones that came with the kit, i heard that makes it a little more stiff, but they last forever. I got mine from blueovalindustries.com best price i could find, and i got the bushings from somewhere in CA. Mustang restoration or something. The suspension wasn't bad, there is a really good article on corrall.net. My only complaint is that the front wasn't quite lowered as much as the rear was. But its barely noticable and i havn't had any trouble with bottoming out or anything which is always a problem on a lowered car. The car still launches great and handles even better. The rear swaybar that comes with the bullit kit isn't as thick as the GT kit, but supposedly they are tuned to work togather. I kept he GT swaybar cause if it is stiffer it could be installed if you are looking for more oversteer. The car right now is very neutral feeling. It was well worth the 400 or so it cost to install it.
