Thanks. I am not entirely sure about VR. In fact, I am purchasing for watching 3D videos, instead of gaming, which one is for me? canThere are a number of differences between the various headsets. If you're looking at gaming in VR, then the first thing you need to know is if the game(s) you're interested in is even supported by the headset you want to purchase. Now I use Steam to keep an eye on what is new and available for VR headsets and Steam does a decent job of tracking what headset can be used for each game. They break it down into three groups:
Windows Mixed Reality
For both Oculus and HTC, their headsets are their primary focus. These are also the more expensive headsets, but they have dedicated support teams in house. The Windows Mixed Reality sets have hardware developed by a multitude of developers; all working on the premise that Microsoft will maintain development for their Mixed Reality realm. However, if Microsoft decides it's just not the right time (i.e. they're not making enough money from it), they could pull the plug at any moment (just like Windows Media Center or any Windows XP supported Hardware).
The other major difference is that both the Rift and the Vive (and variations of) also require external sensors (included in the price) to track you in a 3D space. The Windows Mixed Reality hand controllers have the 3D tracking sensors built in. Not having used either the Rift or Vive, I can't say which set up is better.
I looked at it this way: If you're not entirely sure about VR, then I would consider the cheaper solution just so I could get an idea of what it's like. If that convinced me, then I would go ahead and then make the more expensive purchase. If you're absolutely sure about VR, then I would definitely recommend on of the more expensive head sets (Rift/Vive variants).