So, down at the play expo yesterday, there was a rift setup, queue was massive though so I didn't bother, and at the back, there was a guy showing off a game he made with a rift, so I went on there instead.
I thought it worked well, and responsive, but it was like you were staring at an 80s TV from an inch away where you could see all the physical picture elements, and the resolution seemed quite low. My missus couldn't adjust and was a bit unsteady after taking it off, but I was generally okay, was a little weird.
That all said, I am tempted to get one, but maybe a bit later down the road. I'd recommend trying it if you get the chance though