In S4 I would say approximately 30-40% of the filed are on 30mm chassis. S2 might actually be closer to 50/50. I always ran a 32 until last year. I switched to the DR 30mm chassis and it works better for me than any other chassis I have driven in (S4). I’m also 6’4″. Most people you ask would say I need a 32mm, but that isn’t the case.