I know of some guys who race GG 300's. They use all OEM GG Fibers but then add just 1 CRF450 fiber at the outside (last one) of the stack. Supposed to provide a bit more hook up on the clutch.....
That being said that is for manual clutches only.
As for your Rekluse - I would recommend to use GG OEM. Otherwise you might mess up the "Installed Gap" dimension that Rekluse recommends in order for their EXP to work properly.