This version seems smoother / less severe, though obviously not tried as much yet, but if the consumer version is improved as much again as this seems to be I think it'll be ok.
I've not heard of that one, though there was another one where you're just at a desk and can look around - no dolphins or cheating.
I saw something today about a Mozilla JS plugin thing that can work with Cinema 4D scenes in the browser... not yet looked into details, but it does mean if I ever get my website done it should be relatively simple to add a Rift mode, which is cool.