i wear a size 10 burton prvt stock boot....
i wear a size 10 burton prvt stock boot. will the large binding will b too big?
Nope, that is the size for your boot.
With a size 10 boot you are right on the edge of a medium binding and a large binding. If you want to easily jump in and out of the bindings and don't mind a little wiggle room, then go with the large bindings, if you want to spend a little extra effort adjusting straps and getting into the binding for super snug fit, then go with the medium bindings. All and all take your boots into a shop and test em out before you buy!