Here are my results.
Now all of this involved no thorough testing as you did with the latency but more so feel of the games.
CS:GO with SLI disabled did feel a bit better. I found myself having to reload the game and check the difference between nosync and gsync. I did a blind test with a friend, I was able to correctly guess which one was nosync each time (5/5), but it wasn't easy. I still say this is because any increase in input delay would be noticeable by me based on the hours I have played in that game. Anyone that had not put in the hours would be very happy with the results.
Splinter Cell Blacklist Didn't want to work well in SLI, but with single card did manage to iron out a stutter or two. This wasn't that impressive for the price tag, but I could still tell when Gsync was on vs off. This was also hurt by the fact that I'm used to the game at 120FPS+ so seeing it at 75-80 was just not as smooth to me, even with gsync.
Loadout - played the same, game only uses 1 card anyways. Gsync did remove maybe a stutter or two, but I had to actively switch between them to try and find the difference
Battlefield 4 - Stutters were gone, and while I could see the effect of gsync at the lower Frame Rate of 60-70 in the Single Player mode (Ultra) it wasn't as smooth as the 120+ I usually would get in single player or the 144 constant in multi-player with SLI.
I would definitely say there are still serious SLI issues that need to be worked out, and as someone who spent a lot on SLI it was sad to see. I understand they will work on it, but thinking of when Battlefield 4 (when it wasn't crashing) had a horrible micro stutter like older SLI setups would have. This made me very weary of the implementation of the technology with dual cards. So for the time I reverted back to the original monitor and packaged up the Gsync for return. I'm just not happy with the results at this point, and apparently don't have what it takes to be an early adopter for my setup. I do wish all of you the best with yours and I'm glad you are having better experiences.
One last thing, Chief, you do mention about fixing the backlight bleed on the edge. I do feel this was from me putting the shell back on the monitor too hard, maybe? It definitely wasn't there before, and now I can't take my eyes off of it when the screen goes dark. Are there any guides to what you were explaining with tape or the screws? That would save me from buying a new monitor in the near future. (Yes I know that is crazy for a little backlight bleeding, but I get hyper obsessive over it).
I'm thinking the bleed you are talking about would be one seen through the edge of the screen, where mine seems to almost create a 1/4" frame around it where it is clearly brighter now. Same effect as if you were to squeeze your bezel just a little on a dark screen and see some bright spots for the moment. If this is fixable in any way, I'll tape the crap out of it inside
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Great community, seriously, best wishes for you all.