If you are looking at used, the 8UAF is the older model of the 8UAFS. The S on the end means super and has 8 model memory (might only be 6, I can't remember). The 8UAF only has one model memory. The 8UAFS also has a removable module in back for the freq. The older model doesn't have it. The 9C is a way better radio, just for your information. If you are even close to the same price, you would be better off with it. I had both 8 ch modles you asked about and sold them when the 9C came out. Much better radio.