I would not use sewn in armour in any race or rally! my 661 pressure suit saved my ass last year and it took a few hours and hundreds of stitches for me to repair it. Essentially the crash and subsequent pounding tried to rip the suit right off, the fact that it was held in place for the initial impacts likely saved my forearms which took the brunt of it.
I would rather deal with Chafe than broken bones....
my 2cents :)
XR650R dualsport/Rally Trainer
“We should come home from adventures, and perils, and discoveries every day with new experience and character”