(Sorry for the quality, almost no light there)
The version I tried was the Developer Kit 2 which is the last out, of course only for developers. I couldn't play, just watch an animation, but fair enough.
The animation was about a roller coaster (Riftcoaster), you can see it Youtube here . The feeling was quite good, in fact it was real enough to make me feel some "virtual altitude sickness" in the higher points of the attraction. The fluency of the animation as you move your head around was very good and real.
However, I found a terrible fail that prevent more enjoyment. The screens inside the glasses had a very low pixel density which almost destroy the experience. If you look carefully, they resemble those old CRT TVs where you could count the pixels if you looked close.
To show you more or less how you really see inside, I've edited a picture.
Click to zoom it. Although you forget this error to pay attention to the video, it's something that must be improved quite a lot.
By the way, I can't remember about the black edges, so they probably aren't something to worry about.
Try them if you can, it's a nice experience.