The G201 is a 10microstep drive and the G210 is selectable, so you can run at different microstep amounts 10 and under. I beleve theres an addon chip for the G201 to convert it to a G210.
I just stuck with the G201 because I want the best precision I can, I beleve you can get higher rapid rates on less microsteps, but its not selectable by software.
With those motors, if you want a rapid rate over 35ipm, youll want a higher voltage power supply than 30v, you can go up to 80v with the geckos and possibly get 120ipm without much problem on 5tpi ballscrews
Btw, I sent you a PM