Breathability - I never really thought about it. The toebox is pretty open...the rest of the shoe...I don't have them in front of me, but I think okay. I didn't ride them in any super hot 30+ conditions...but they've never felt like they were excessively hot or anything like that. I tend to have pretty sweaty feet too. So, pretty good?
Sole Support - They feel really substantial. But with one freerider pro on one foot, and one of these on the other, I didn't feel a lot of difference. I thought there would be more difference, even just in the thickness of the sole. I think there is more to these, but not a world of difference than a freerider pro. They're not as clunky as impacts. Somewhere in the middle of those two things. One thing I thought about mentioning but didn't, is you can see from the marks on the sole that I ride these pretty far outboard...like the whole outside of my foot is off the pedal. it's further out than on my Freerider Pros. I think this is because there is really great support. I can run my foot as far outboard as I need to. Make sense?