I use a spokeshave exclusively, like said above make sure it's very sharp and don't set it with too much blade sticking out, if you get chatter (the rough surface) then raise the blade up, don't force it either, pull it towards you letting the tool cut, I often times start on the corner not on the flat surface in the center of the stave or board, angle the spokeshave to shave the corner pulling towards you, then move a little more towards the center and pull towards you, then move a little more until you've worked yourself across the wood, spoke shaves aren't really designed for really flat surfaces, remember they were used to carve spokes. Take your time and learn to use it and you'll reach for it every time, I do.
VB