I just had a quick go on a mates rig with a HTC VR headset. I didn't know he was filming me, but because he did, I thought people might be interested in seeing it in action...
INCREDIBLE. I highly recommend it. (As you can see, my mouth was embarrassingly wide open with awe and wonder at how real it was...)
Only downside is that you loose the ability to zoom in as you do with a head tracker and you can see a slight fine texture on the lenses you are looking through. I got a bit airsick too.
Tracking opponents in a dogfight is much easier and the rendering of the cockpit gauges and aircraft are amazing. It feels REAL. You will probably need a full hotas joystick/throttle combo as you can't see under the goggles to use keyboard. I'm sold on it though. Awesome fun! It takes things to the next level.