OK, I tried it at a sci fi con... the guy demoing actually knew less about it than me sadly, so was not of much help.

They didn't have anything good to demo with... but they did have some cheesy low res space sim that was a good enough stand in for SC and E: D (yep, backed both, love both)

What I liked;
It was more comfortable than I thought it would be
The motion tracking was SUPERB, smooth and accurate near as I can tell
no hint of motion sickness (I am not prone to that anyway)
Calibrated easily

What I did not like...

The dreaded screen door effect. It was gawdawful. ruined it for me. To the point I was sooooo glad I didn't take the plunge and get a dev kit yet. I don't THINK this had to do with the low res space sim, I think it's a factor of the screens used and magnifying glasses. It was just so pixelated it genuinely irked me. Profound disappointment on my end. I really expected better than that.

I have heard that there will NOT be a DK3, but I have also heard they intend to replace the screens with something better.

If the screens don't improve, I am not even interested in the final consumer version. If what I get is what I experienced, I am going to pass on Rift entirely... I like my triplehead with TrackIR just fine... or maybe check out this Morpheus from Sony... but the screen door effect was a deal breaker for me.

What do the Rift experts know about this problem and what Occulus is going to do to fix it? That's the 'make or break' right there for me.