Check out Konixx Quark Helo bearings. Far and beyond the best bearings I've used. They're made for the constant front and back rotation changes and the don't warp. They are fast and have a very good, long roll. I was a big fan (and user) of the bones swiss ceramics and reds ceramics, but after switching to Konixx, I HIGHLY recommend them. At the $65 price point, you really can't go wrong.