I am usually a size 6.5 in shoes, so I had bought a size 6.5, but it was too small. I then sent it back (very easy refund process btw) and purchased a half size up to size 7.
The size 7 on my (wider than typical) bare feet feels narrow and right now fits comfortably snug. I don't think I'll need to be wearing socks while wearing these as they are very warm. The inside of the shoes are soft and does not rub the heel/sides of my feet painfully, no breaking in period required! The soles squeak on my polished cement and wooden floors, its hilarious now, but we'll see down the track.