Another vote for the Lyman with auto flow. You will still have some media in the cases, but after I drain, I take the lid off, turn the tumbler back on and use my hand to help turn the cases, to get the rest of the media out of 'em.
With my RCBS Sidewinder, in addition to the Formula 1 Walnut Shell Media, I got a packet of polish material and the two together seem to work really well. Curious though, when you add the Nu Finish car wax, how much do you add in and to roughly what quantity of Walnut shell?I use a Lyman,and like some others buy walnut shells from Acklands.I use Nu Finish car wax in the media .Cases come out clean and shiney