Has anyone ever used this product (http://www.restoreusa.com/restorer.html) the engine restorer that you can buy at the local parts store. A guy at work that drives a 96 cobra uses it, and swears by it. Then again, someone else said its like slick 50, and slick 50 completley ****ed up his motor. So I'm a little hesitant to use with the second opinion ive heard, so has anyone else heard anything about this product, or even used it? if so how did it work?