I'm certainly no guru, but here's one man's experience.
I had been using Dell business class IPS monitors for years and years; first a 24" 16:10 ratio and then a 30" 16:10. I LOVED these monitors. When I finally decided to upgrade I hesitantly went with an Agon AG352UCG G-Sync monitor. It uses the same panel as a number of other 35" ultrawide MVA monitors with a resolution of 3440x1440.
I say "hesitantly" above because I was VERY unsure about stepping away from my beloved IPS panels and into something that was potentially not as good. All I can say is that I have been happy in every single way with the decision. I use the monitor for 95% business as opposed to gaming despite having actually bought it for gaming purposes. The colors, clarity, and precision are all everything I could have hoped for.
Monitors are subjective and I know some of the reviews of MVA panels mention various uniforminty issues, etc. I'm either not as sensitive to those problems or they don't exist in my unit as to me it seems perfect from one end to the other. I'd have no problem recommending one of the several monitors using this panel. I'm typing this message on it right now and it prompted me to re-examine the angles and colors. They still look good to me.
For what its' worth I originally powered it with a GTX 970. That was "ok". The G-Sync kept everything playable even with lower framerates, but when I upgraded to a GTX 1080 a few months later it was a marked improvement. I'm no GPU expert but the improvement was actually way more than it should have been given the actual difference in GPU power and I suspect strongly that a big percentage of the difference was actually the higher memory count in the 1080 over the 970. So if that's true, it's a good reason to consider a high memory card, even with a smaller GPU if going for something with 3k or 4k resolution.