can anyone tell me if there's much of a performance difference between a slip-on silencer or a full exhaust system. I don't have a lot of money to spend so I've been looking at slip-ons. Will slip-ons make a difference in performance? Also if anyone has any suggestions of a make and model of exhaust that will improve all around performance and is good quality at a decent price, I would appreciate suggestions. I have a 2005 crf250r.