I installed a set of the baffles from SmartPartz in my HK 2.5" Strippers over the weekend and I have to say I'm pretty pleased overall. They don't really make it any quieter but they do deepen the tone which is much more pleasing in my opinion. They were just too harsh before, especially with a full face helmet on. The only thing I don't like is that with the Strippers you can see the baffles stuck right in the end of the pipe and it looks a little cheesy. I'm thinking of maybe painting the baffles with a high temp black to camouflage them a little, but then again maybe they'll do that on their own with a little carbon buildup over time. Oh and $9.99 shipping and they got from Cali to Ga in 3 days which is a pretty sweet deal.