I'm sure you guys are already aware, but in case you missed it, Syl Arena has confirmed that HSS works perfectly well on the 5DII with the 600EX's. I'm not sure why Canon stated the contrary.
I really like how the 600EX notifies when all your slaves have recycled, I think that's an amazing feature. In Chuck Westfall's video he shows off a few different ways you can interact with the master and slaves via the camera body, I thought it was impressive. Overall, if you're big into OCF then Canon's system really is an amazing option. Unfortunately, if your into OCF you're already heavily invested in speedlites and triggers
As for the 5DIII, I think it's really solid, but I'm underwhelmed. I think for the price Canon should have included professional weather sealing and a professional metering system.
D800, D700, MB D10, 85 1.4G, 70-200 2.8G VR II, 16-35 f4G VR II, 60 2.8G Micro, SB 910 (x4), SB 900, Radio Popper PX Trans (x2), Radio Popper PX Rec (x3)