I have the Oculus Rift Dev2.0, awesome experience, if it didn't make me want to puke after 5 minutes. But that is my problem ;-)
The immersion is immense and that is with the older model, the new stuff is supposed to be amazing!
On the CES 2016 both models were available, according to folks both the Rift and the Vive have virtually the same experience when we're talking about the visuals. There are some differences in the extra's, the Vive has Roomtracking and an internal camera. But the Rift is already $599/€699 without controllers and it's being sold at cost, so the Vive with the camera and controllers will certainly be even more expensive. The Sony one for the PS4 is still an unknown entity, assuming they use the same hardware for a similar experience, they also seem to be adding an additional external device to boost graphics performance. That's going to cost a pretty penny unless Sony is going to subsidize that device... Either that or it's going to be a lesser experience compared to the Rift/Vive... Don't know about any issues with tracking that the Vive has and the Rift doesn't have...
It's quite expensive, especially if your not used to paying a lot for PC hardware. But keep in mind that this needs at least a GTX970, a €350 video card. And if you want a HOTAS + rudder setup for those flight/space/mech sims, that can easily set you back another €500. Playing on a keyboard is a pain at best, although a controller works fine.
Personally I'm waiting on comparitive reviews of the Rift and the Vive upon release (from multiple trusted sources), before I replace my Rift Dev2.0 with the higher quality production model. But my preference is the Oculus.