I'm going to get started cutting off the excess brackets as part of my street tracker project. I was going to buy an 5 inch angle grinder along with a cut off wheel and a variety of grinding wheels. Then I starting looking at die grinders. They run at much higher RPM's and seem to be generally suited for smaller and more finely tuned work. There seems to be a lot of accessory cut off and grinding accessories for the die grinders - probably more than for angle grinders. The die grinders are generally pneumatic whereas the angle grinders are usually electric. I'm ok with either. And, I like to buy good quality tools; I hate junk. For those that have hacked your frames and used either an angle or a die grinder ( or preferably both ), I'd be interested in your comments and recommendations.