What is the difference in power gains between a slip on and a full exhaust? is it very noticable? Right now i have an uni air filter, alba programmer and a two brothers slip on. I'm debating on selling my slip on to my friend and buying a full barkers exhaust but i'm only gonna do that if you can really feel the difference in performance. I really like the way my two brothers sounds but i'm really wanting more power. whats yalls opinion?