I researched the SCX vs bmax a few years ago, EVERYONE I know lost speed with the SCX. (plus their customer service and warranty work is atrocious). I talked with john at the bravo shop, he said if HE set the drive up you won't lose any speed. We changed the gear ratio slightly from 1.36 to 1.38, I run the bmax upper and the IMCO lower. I didn't lose any speed at all. I run 850+ on a 28' Nordic, went low 90's before, goes low 90's now.

The bmax is nothing like the XR, the case is literally twice as wide as an XR case and houses enormous helical cut gears. (it retains the merc cone clutch for shifting, however). Plenty of people running 1000+ with them.

Its kinda ugly, where the SCX is a nicer looking piece imo. I wanted to go fast though, not look cool at the boat ramp.