I would also consider the Tekno conversion it uses a clutch so it does not put as much stress on the front bearing of the motor when breaking since it uses mechanical breaking. I know some people who have not been around the setup think it sounds stupid, but I have the conversion on my Losi 8ight T and love it. It seems to make it a little more controllable than some of the other conversions I have seen. I have not driven any of the other conversions and do not mean to step on anyone's toes though.
Impakt RC has most of the above mentioned items on their website.
http://www.impaktrc.com/index.php?cPath=238