There are few varibles to consider to pick one of thses strokers. The 446 from FST uses a longer stroke at 75mm and will lower your revability a bit as the piston speeds will be higher. If I remember right 8500 rpm will be it. It isn't much better with the CWR, they use a 74mm stroke and you'll gain about 300rpm. The biggest difference will be service, Mickey puts regular customers on the back burner until he has taken care of the racers that use him, plus he is very buzy and will get to it in the order it came in. Example I sent the cases, cylinder, crank and head to be done on November 17, I didn't get it back until around January 28. You can only call FST on Monday to Friday 4PM to 7PM and the line is always buzy. If I had to it over again I would of gone with CWR.