So I have spent a couple of days with the monitor now and have got to the bottom of the issues I was having. Anyone getting one of these monitors new you need to heed the following:
1) If you are coming from 1080p you'll be changing settings, restart the game after you do it! The Nvidia gsync drivers don't seem to like changes in resolution, anything that causes the monitor to reset its mode can cause issues. In game it'll show stutter or worse performance, something a game restart will solve.
2) Almost all games are better with vsync in the options set to off. Some games seem to do frame capping when vsync is on, setting to 60hz usually and you want to avoid that. I have also found in Arma 3 it causes some input lag which isn't there with vsync off. But just like (1) changing and then using it straight away sometimes doesn't turn out so good. I blame the drivers, bad Nvidia hasn't tested that scenario and it shows.
3) Reinstall your Nvidia drivers after the install of the monitor. For whatever reason my games did not perform right until the driver was reinstalled. Metro last light was the first example but the Crew beta also suffered.
The odd thing that has happened this week as graphics settings have been going up. I had gotten used to running at 60+ hz all the time (vsync off) for smoothness shake on my Benq XL2411T and having used gsync for a while I can say I am pretty happy at 50hz or more with gsync and maybe as low as 40 in some games like Arma 3. So quite a few games (Tomb Raider, Metro Last Light, Witcher 2) now all look quite a bit better with higher quality settings and gsync has allowed that to happen. Even playing BF4 where I like really high frame rates I have gone from 120-170 fps to 70-90 with some improved AA that reduces the crawl in the distance and the higher resolution and don't notice the difference in performance. I can't take it down to 50 ish however because the thing I want more of is AA and I am hitting into VRAM limits.
Its definitely an improvement over vsync. There is still some game stutter here and there, but at least now I know its the game (looking at you Tomb Raider!) not the GPU. I don't notice big reductions in frame rate now, and they are definitely happening they just aren't important any more. I can now use Nvidia's recommend settings for games and never really have a problem. 30 hz still isn't smooth, its more playable to drop into the 30-40 range than it was with vsync on or off but its still not pleasant. The one thing the crew has taught me is just how bad 30hz really is, I can't believe the console guys are happy with that because on this monitor 30hz locked doesn't look good, its not stuttering its just really obvious its low frame rate. I do run with motion blur and such off which only makes low frame rate that much worse but that game better not come locked to 30 out of the box!
Colour quality is significantly better than the Benq before. Its a lot more vibrant and it also supports a lower brightness so I can run it at the brightness I want without messing with anything else. Its definitely better than the Dell 2410. The static image compared to the IPS is about the same, I can't tell any quality difference by eye but when the game is moving its so obvious how good the blur reduction is on this monitor. Its a little better than the Benq in that department, there is a little less overshoot so the image is a bit sharper. Enormously sharper than the Dell of course but also better than the light boost 2 monitor.
All in all it meets its tag line, ultimate gamers monitor for an extortionate price.