Ive searched and as many people have the same issue..
Stick with the 600 and dyno map it, or swap in a 750 and sell the 600 engine and dyno map it after. Its $250 to custom tune it. Or stick with the 600 for another season and 750 it later. and remap. Feel that is a waste to remap.
I feel like I should swap to the 750 but also wont know what engine I will be getting etc. I know my 600 works great. Only ride street, small city of Reno,NV. high desert/mountain twistys all over. 600s everywhere here, but the 750 seems nice.
its not worth all the work for 20hp. tune the 600 or get a different sprocket gearing. i run 15/43 set-up and i like it. most people who want more acceleration go with 15/45. its cheap and adds a lot of peep.