I got my new card today.
Not bad, considering it wasn't supposed to be in stock until yesterday and I picked free super-saving shipping.
Here are some performance numbers:
The existing settings were 2560x1440 High 1.5xSS V-sync (dual GTX 970 SLI). I was maintaining about 60FPS in space, dropping in stations and on planets. I turned off V-sync to see what happened. The second set of numbers are with 2xSS. Numbers are FPS.
Inside Station (bit lower in hangar): 75-85 / 50-60
Outside Near Station: 130-150 / 60-70
In Space & SC: 160-175 / 100-115
Planetary Landing: 90-110 / 50-60
Driving SRV: 70-90 / 40-50 (higher with lights off)
The temperature was typically about 70C and the fans were pretty loud.
Then I turned V-sync back on and headed for the RES. Once I left the station, the FPS never dropped below 60, no matter how many ships and asteroids were about. The temp dropped to about 65C and the fans were pretty quiet. 2x super sampling looks awesome, but I don't like the frame drops in the station and on the planet, so I dropped SS back to 1.5 and increased quality to ultra. Now it's holding 60FPS even in the hangar. I really can't tell much of a difference between high and ultra.
Everything is very smooth. I haven't checked, but the SLI related glitches should be gone. Now I just need to get my HMD. It's supposed to start shipping next Friday, so hopefully I'll have it within a couple weeks.