I've seen alot of post for exhaust for the 650l, but not alot for my pig. Which exhaust is the best for the 650r? I'm torn between some type of FMF and a White brothers. Also should I keep the stock header(and wrap it) or go with the oversize. What's the valve-stress level at with a larger header? Any backpressure issues? Sound is kind of an issue but most all companies make a quiet tip insert. Anyone seen a shootout?? TIA.