Yeah they're right. Purpose of a jet kit is to fine tune your machine. You will get better starting and throttle response from a jet kit, but will not increase your power. All the kits out there are just rebadged DynoJet. I have been frustrated many times trying to get adjustments right. Seems like DJ is always rich. If you like to tinker and understand the workings of the carb then go for it. If you like to tinker and want to learn than go for it. If you want to just install kit according to instructions and expect machine to be spot on.................. than forget it.