Sold the BK5 so now I'm considering an alternate setup to keep around. The Privia PX350 keeps piquing my interest. But I do have some questions.

1. How are the built-in rhythms? I only use a few now on my s950 - big band, country 2-step, 6/8 Rock Soul, and a couple more. What do the Privia rhythms sound like? What about variations, starts and stops?
2. What about MIDI/mp3 playback? I rely heavily on midi and am getting into mp3. What kind of system do they use? Is it pretty straightforward or is it too simple or difficult to use?
3. What about onboard controls? What works well and what doesn't?

At $800 or less, just the piano stuff is interesting, but could I use it on a gig and not make a fool of myself trying to use the rhythm section and the USB MIDI playback off the sequencer. I'm looking for some YouTube demos, but they're hard to come by. If anyone has any knowledge or experience with the 350 or the previous 330 series, please help.