I haven't used one in about 4-5 years. I had one board (Option Mirror) with a matte topsheet and thought I'd give it a jam without buying a stomp pad. It was fine, and I could skate, turn and ollie pretty well without any help. So when I got my next board, again I thought I'd leave the pad off and see how I went. 3 boards later, no stomp pad, no worries!
For turning, I use the toe of my rear foot to pressure the toeside or heelside edge and can control things pretty well as long as you keep your knees bent. If I'm cruising on a flat groomer I actually find it more stable to keep my free foot closer to the front foot instead of jammed up against the rear binding.
My favourite trick now on long open groomers is to unstrap, and then bring my back foot around behind the front foot onto the nose of the board, then pressure it into a nosepress. So fun, and when it goes bad, it looks really awkward
