You can also use (and I have used) a "3M Headlight Restoration Kit" from your local automotive store. it comes with a drill mounted arbor and sponge for applying their white polish, and several grades of sanding pads. But micromesh is better ;-)
Magic eraser works fine too. I've only had to use the oxyclean once on a very very abused stem. Micromesh is good to remove scratches and teeth chatter. I've cleaned up 20 or so stems and there is still plenty of life left in the mocromesh pads.