I have vorpX (something I got back when I got the Oculus DK2 for Christmas). I didn't really use it much because it didn't seem to work all that well.
However, Oculus recently updated their runtime and now vorpX is working. Sort of. I am having FOV issues with it and everything feels too zoomed in no matter what setting I use. But it DOES work on non-VR games such as "Alien: Isolation". If I could get the FOV working correctly, it'd be great. However, the mouse controls were connected to the head tracking and that might get quickly cumbersome to aim. Not so much in Alien: Isolation but definitely in Half-Life 2 (the two games I've tried it on so far).
That's something they need to fix.
And I know it can be done because I have seen it. Back when SteamVR was first getting off the ground, they had "native support" for Half-Life 2. It worked pretty well. I got from the beginning (the G-Man sequence didn't really work, but the rest did) all the way to the airboat without getting sick even once (except at the loading screens--I'll come back to that). But then the airboat FOV was all fouled up. Valve released an update later and the airboat FOV was fixed. I played through until you had to fight the gunship underneath the large bridge when SteamVR updated again and broke "native support" for Half-Life 2. And it hasn't worked "natively" since. CURSES!
However, when it DID work, it was beautiful. And the mouse controls, meaning weapon aiming, was uncoupled from my head tracking allowing me to aim naturally with the mouse. I thought it would be cumbersome at first, but I was surprised at how natural it felt. I became a crack shot really quickly--far more accurate than I've been with mouse aiming on a 2D monitor.
I would really love to try the Vive in Half-Life 2 with the controllers. Hopefully it works there.
As for the motion sickness, that can come with a lower frame rate. Even beefy computers aren't quite up to the task of TWO high-def displays at a high refresh rate yet.
When I was running Half-Life 2 with "native support", whenever I came to a loading screen, I suddenly got very dizzy because the world stopped moving but I didn't. I felt like I was tripping over something and everything started spinning briefly. I got sick as a dog at every loading screen. I had to remember that a loading screen was coming up and quickly shut my eyes whenever I got to it so I wouldn't get sick.
However vorpX seems to have come up with a solution. At loading screens, it would stick you seamlessly in a "VR theater" of sorts where whatever you were looking at is now on a huge 3D screen and if your head turns, you're not as jostled around by the sudden lack of movement. It worked very well. VorpX also allows you to enter that "VR theater" at any time by pressing the middle mouse button (assuming you don't have that bound for something else) so you can read menus or whatever else without eye strain.
VR still has a way to go, but the problems that are mentioned are going to be solved and probably fairly quickly. Within 3 years, I bet most of the problems cited will be fixed.
