have any you guys notice a diff between the mod and a pipe such as HMF are the benifits worth the money or not? My riding partner has a Rincon and put on the hmf sounds awesome and he said he could really notice a diff in power in the low end

 

I have one friend who has been switching back and forth between the mod and a T4 trying to see the difference. There's not alot except the T4 is very expensive and much louder.