i have one friend who has a 03 z400, another who has the 05 trx450, and his dad has an 01 rapter. the z400 was handin out ass whippins at the dunes with a yosi, jet kit and k&n, the rapter had the same and the 450 was stock. after that weekend, the rapter got a 11.1 piston stage one cam's and a set of alba transmision gears, the 450 got k&n's, a jet kit and trinity stage four exaust. needless to say, the 450 took the prize, the raptor was second and the z was a close third. i am talkin about spliting hairs here. at any rate i still fly by them all and have a great time siting at camp, and hearing them bitch about all the sand they ate which was coming off my tires. i say keep the banshee!