personally, i think that if aprilia in stock (rs pipe) condition, loses to SP in stock condition.... then if both are modded (arrow vs HRC), i believe the results will still be the same.

not that i anti-aprilia, just that i pro-SP.

anyway bikes, got alot of things to mod mah.
for SP,
pipes dun say lah, got internal gear ratios, external gear ratios (sprockets), skimmed/racing flywheel, rear hub, light weight rims, cdi, valves, throttle, suspensions, etc.
but then, if u really go mod till like that ah, the money u spent modding is enuff to buy another SP.
then again, money is not no.1, what is no.1 is your desire and your passion.
yes it makes more sense to just buy a faster bike, but passion isn't controlled by neither logic nor common sense.

------------------
vroom...
pissssssssh...
chik chik...
vrooooooooooooooooooooooom
tingtingtingtingtingtingtingtingtingtingtingtingtingting