Hi there,
if it was up to me, I'd go the reverse,I have ridden one with the reverse on it and it went real well.
I think that Giannelli make one that bolts straight on too,but I'm not 100% sure,if not I think its only a mounting bracket mod.Giannelli make, I think one of the best pipes for the r50x,,,THE REVERSE.
GOOD LUCK WITH IT,,,,,,,,ENJOY THE RIDE