I’m going to honest here. I own this exact model year. I hear virtually no appreciable difference. Other that the placebo effect I bet you only gained maybe 1-2 hp. All that for probably $500 worth of upgrade to install. My son had a 05’ 636 with a Yoshi pipe and he according to stats had 12 hp more. Yet he never once out ran me, < 07’ 599 with rider mod and $500 in his pocket.