I JUST bought one of these, and it's been running just fine with an FX-6300. I ran a series of benchmarks with 3D Mark, as well as playing some Crysis 2, and several hours of Battlefield 4. I've had none of the VRM issues (which is the most discussed issue I've seen for this board...) that I've seen around. I also have Revision 4 of the board.
Obviously, your experience could be different with the 8320. But I saw reviews of overclocked 4300s being throttled, so I don't know.