There is no breathability with these slippers.
They make my feat sweat horribly with bare feat, but almost not at all while wearing socks. Maybe it's just me.

I ordered these as an Amazon deal, and got them relatively cheap. The construction is great. The overall appearance is great. And they are super comfy. The hard sole is great if you need to run out side real quick. It's supportive, not slippery on our hardwood or tile floors, and light weight.

I really do like these slippers and recommend them, I just wish I could wear them with bare feet and not have my feet sweat. Maybe a couple little vent holes on the side would help with this.