They are nice numbers on the dyno. How much did it cost you? I bought a set of TK pipes from Australia. Removed the air intake snorkel and fitted the tk pipes and got 47hp on the dyno. To confirm this Kev has seen the bike and seen the dyno sheet. I am not taking away from dna filters they make a great product but there is options. The TK pipes are around $900 aus. With this you get a single exhaust on the left and a exhaust/tool tube on the right very handy as it holds two tubes and tools. The pipes are made out of aluminium and are ceramicoted. Terry the owner of TK pipes previously was the manufacturer of GYTR pipes for Yamaha.