I recently ordered these and am really happy with them.

Fit: I was a little concerned about fit based on the conflicting reviews and was unsure what size to order. I normally wear a size 7 and my foot is medium width, maybe a bit wide across the toes. The size 7B (medium width) fits perfectly. They were a bit snug to get on the first time or two, but once on fit perfectly with a thin sock. After stretching a little as every slipper does, thicker socks weren't a problem. Not everyone's foot is the same, so I guess that explains why so many find this to be too small. But my normal shoe size (what I wear in Nike, Adidas, Keens, Clarks, Eastland, Born, etc) is the size that fits me in this slipper.

Arch Support: I have a pretty high arch and these support that right now. I will update if that changes as the shoes age and possibly flatten out a bit.

General Support: These have a more structured sole than my Woolrich and Acorn slippers have. While they all have a rubber sole, these are a bit more solid, which seems to give my foot the support it needs following a stress fracture several years ago. I find with some slippers my feet will ache after a bit and that doesn't happen with these. They aren't so structured on the bottom that you feel like you are wearing an actual shoe, however. It is a really good balance of structure/support and softness/comfort.

I will update my review if there are any issues. I definitely recommend them!