I don't know alot but here is what I think I know... I believe the XR is rated somewhere around 600 hp. Which has sraight cut splines. I have been running a bravo for a couple years now with a blown 509 with no problems. It all depends on how you drive it. I think that the Bravo X is basically just the plain old Bravo in a new case. Search the web a little and I am sure you could find some sort of spec sheet.