Finally got around to getting this set up last night, and played a few things off the demo disc and Worlds.
I generally like the headset a lot. It's comfortable, the screen door effect is pretty minimal, and overall it's a nice piece of hardware. My only real problem is that there's a bit too much light leak around the edges (I'm willing to concede more adjustment might fix this, but where it feel comfortable lets light in around the sides).
The real problem I have so far is tracking. I've played a lot of Vive games, and I've had a few tracking issues with the controllers (never the headset), but it's relatively rare, and the vast majority of the time, they're rock solid. Here, the controllers are flaky the majority of the time. Yeah, they're usable, but if you go from the Vive to this, the fidelity drop is really noticeable. To be clear, I'm not talking about them getting way off, I'm talking about the jitter I've seen a lot of people mention. You can still control things, but going from the very precise tracking of the Vive, it's jarring.
The headset tracking issues are smaller, but almost worse. During one part of the London Heist (the desk shootout), the whole thing just started pulsing back and forth in front of me, which was really unpleasant.
I know why they went with this tracking solution, but boy does it feel like a step down from the other sets on the market.
Also, before you get to the shooting, London Heist is sort of bad. The interrogation scenes are silly because you're disembodied hands, and the meeting in the bar is weird because it lets you pick up all this stuff, but no one responds to anything you do with it. The shooting stuff is well conceived, though.
On the other hand, the lineup is interesting, and I have a bunch more stuff I want to take a look at. I suspect the tracking issues will be less noticeable with games where you're moving more often, since it's a relatively small wobble. Also, I'm just glad to see more companies involved with this stuff, and it's definitely a more consumer friendly version of this technology.
One last minor annoyance (not really VR related): they let you play parts of Worlds while the rest is installing, but it screws up the experience. The sound kept dropping out while I was doing the "Shark Encounter". It was fine after the install was complete (once the disk stopped spinning), but it's a bummer for the first experience with the hardware.