Check with Lushy, he does a nice drop in, bolt in cam, that requires pretty much the absolute minimum amount of fuss to get working right.
Price is good, if I recall right it's good for about 8-10 whp, paired with a good header it'll make fantastic power across the whole RPM range.
Honestly, I'd strongly suggest the Carpenter clutch springs. Much stronger than others, but not horrid on the hand.
Regarding riding twisties and torque placement, really its about this:
Do you want to EXPLODE out of corners or smoothly accelerate out. 99% probably just want a good rush of torque on the way out of the corner, for those who want to launch off the corner exit, high RPM power is the way to go. 60mph through a tight corner, rolling on quickly as you apex and hitting full throttle just as you start to stand the bike up in 2nd gear on an incredible experience, one I reckon would scare a lot of people off the bike, and one that will easily end in a high side if not done smoothly!