I like my Green T turntable. It's a stand-alone (not table top). I got a square top which is awkward for banging into the knees while turning, but nice for having space for your tools at the corners. They are expensive, but well made and heavy duty for big trees.
Looking for a good table top turntable now...might try the "Basic Bonsai Turntable" Eastern Leaf offers - looks like the one above. But any recommendations for table top turntables would be helpful!