The consensus elsewhere seems to be that 27” wheels have a little better rollover capability than similar 26” wheels. As the 27”ers have a bigger diameter, that doesn’t surprise me. For the same reason (and, perhaps, having more weight), though, it would seem that 27”ers would be harder to accelerate. I’m Ok with the way my 26”ers roll over things and wouldn’t want to move to something harder to accelerate (it’s hard enough as it is). It seems widely accepted that the width of the widest 26” tires gives them the best floatation, which is a rare need here in NJ, but of interest when we do have relatively deep snow. Since I’ve got so much invested in my two 26” wheelsets, I’m not convinced that a move to 27” wheels make sense for me.