out of curiosity once you get ED running well visually in the vive, how is performance compared to on the rift?
Heh, I also don't have a dog in this race (TIL new idiom, thx

), especially given my "beef" with HTC support and a broken HMD in repair for almost a month now

Not that Rift's support is any better, mind you, they're both horrible for such expensive product, which is odd, but I digress.
TL; DR: on the "right" settings, Vive game is smooth on an i5 3570k stock clock + GTX 1070 + 8GB RAM (Elite on HDD, not SSD).
It's hard to say because my Rift experience was very brief and on a 1080 paired with an i7 if memory serves me well, and I have 1070 and i5 3570k. That said, E

station performance tanked in VR in both Rift and Vive on that powerful machine also. Alas, I don't remember the exact VR settings used, because I had limited time and a few games to check on Touch besides Elite. As for me if I remember correctly recently added Asynchronous Time Warp is saving my 1070's and Vive's sorry behind, and FPS stay above 45 which ensures fluid motion and almost no judder. There was a very slight judder when looking at the throttle and hands, when I get my Vive back from RMA I'll see if I can pinpoint the cause (may be something external to the game just tipping the point). I can't check now but I think I have VR high with OpenVR rendering multiplier to 1.2, Elite's Supersampling at 1.0 and HMD quality at 1.25 and the game is running smoothly except that weird judder mentioned when looking at SRV panel.
My personal guess is, Rift's runtime is probably doing something behind the scenes, and doing it much more efficient than Elite's native code. I was initially convinced that the quality is due to somehow better optics, but having set the vive up to the same quality level I think its the runtime or drivers doing very efficient low level quality optimisations.
PS:
Once you see E
on the Rift, you can't unsee it. I wouldn't be able to get back to the initial
Vive jagginess which I have to say
out of the box is horrible compared to Rift's clarity. That said, you can get it to the same quality levels as mentioned, and I find godrays more distracting than vive's lens flares.