If you already have aftermarket head, intake, reeds etc.. your best bet is the cub. You will have to replace all of that if you go with a cheetah. If your starting a build from scratch and buying all those parts anyway then they cost will be pretty close. As far as how much faster? I can't answer that, really depends on your set-up. You may have full blown cheetah and get smoked by a stock bore/stroke banshee. In a perfect world where all things are equal, the cheetah will make more power. It's up to you to put it all together and make it perform at 100%, cause if it's not, a cub will smoke you.