I am height challenged at 66" and experimented in the '70s with 175mm TA cranks and
it was noticeable and annoying compared to 170mm, mainly the slightly larger crank
circle threw me off. The torque variances are small, but larger pedaling circle lead me
rapidly back to 170mm. Altho my ATB is 175, pedaling over wildly varying terrain rather
than smooth asphalt swamps out the difference there, never noticed. A significant
variance is your height, if you are 68-72" especially, you will likely never notice the
change.