When I first got my '09 950T, I wanted to do exhaust, and air cleaner upgrades/changes. The first thing that I did was the 2 "Mods" listed in these forums, drilling out the baffle in the muffler, and adding breather holes in the air cleaner box. I noticed an improvement as soon as I did them. Not night and day, but an improvement. Now as I have put more miles on the bike, 2500 approx, the exhaust seems to be getting louder, still not too loud, and the bike seems to be loosening up, breathing better, performing better, feeling better. So I for one, aren't looking to spend a kajillion dollars on upgrades as of yet. I am a low-cost kind of guy. Just my 2 cents.......