Haven't seen a lot of feedback on these but was really curious about them and ended up buying some yesterday after I added another tube of Goop to my 510 Freeriders. Figured I would document it a bit for anyone else interested. The fit is more like a runner which is comfortable, thin material all around but with well-padded heel-cups to keep the foot down. Still playing with lacing at this time but no real bit issues.
So far I am impressed. I rode them on a rental bike at silver star (Megatower, OMG fun) for their maiden voyage so didn't have the best pedals but this wasn't an issue, typical 510 grip. Had a solid mix of dh laps and some pedaling and they were good on both. I broke my rightfoot years ago and always struggle with that fine balance of stiff, but not too stiff, soles without getting pain or numbness -- these seem to strike that balance. They don't have the sole padding of the Freerider Pros but it doenst seem to matter on drops or jumps.
Also got into a full monsoon and while they did not keep my feet dry they don't absorb like typical skate style shoes. Drying them right now in a boot dryer but don't think it will take long. Longterm longevity is obviously not known now but will report any issues. The hightop version with neoprene cuff are on my radar for shoulder season riding.
It's nice to have the 510 grip without the 510 skate shoe issues.