I have J2 git running under Debian Wheezy on my Pandaboard which is a very similar architecture (armhf) to the RK3066s - 1GB RAM and dual-core ARM cortex A9 CPU.
Yesterday I only had time to set up Cadence and play a few MP3s but today I'm going to see what it can do - which won't be much admittedly.
My Pandaboard, like many of these Android sticks, lacks SATA. SATA would be a big win if you can get a device that has such a port as otherwise the poor USB bus is choked to death with all your devices - HD, audio, ethernet (in the case of my Panda and many other such boards also feature ethernet which is actually a USB device).
If I was buying a RK3066 stick I'd get the Measy u2c which gets good reviews and has an AV port. I'm not sure what to recommend in the way of deb boards with SATA but I know that the cubieboard has SATA and its not the only one but its one of the cheaper options.