polini can be as fast as the big kits but uber delicate.
if ur running a polini 4 pedal and it doesn't go 50 at least with stock gearing something is wrong.
most 4 pedal polinis round here with cheap pipes will hit 55+ on stock or close to stock gearing all day everyday. if ur going for reliability and speed stick with this setup.
add a good pipe and 60+ on stock gears is easy breezy but breaking polinis becomes a real threat. at those rpms.
a well tuned 2 pedal bing setup can do 50+ as well but most only ever see 45 however its good option for reliability as well.
I prefer the white stock polini reed paper in a malossi 4 pedal adapter on my bike
also belief that the malossi 4 pedal is bigger than the polini one is a myth fyi.