While I don't think the Wall/Fox comparison is 100% spot on, it's the best comparison available when comparing UK guards under Cal IMO. Both blazing fast, both incredible athletes, both have the "Wow!" factor when watching them play. Wall was more explosive, Fox is a better defender and more under control.
If Fox finds his jumper, he is going to be some kind of special. I think that day is coming. I know his percentages aren't good, but his shot doesn't look bad and there's nothing there that would lead you to believe he's a long-term bad shooter. I don't feel like it's a bad shot when he shoots an open 3 like I did with Briscoe last year. His 15 foot pullup jumper looks nice, and that's a tough shot pulling up off the dribble at the speed he's moving. I think his shot comes around this year, and when it does the trio of him, Monk, and Briscoe is a serious problem for opponents.