G-sync adds a bit of input lag so if you want the lowest response times you can get then a cheap 120/144 Hz TN is what you want. Personally I prefer IPS and PLS panels, I can't use anything else and enjoy what I'm doing at the same time, TN panels lack color & contrast and look washed out so in a game like Skyrim, you want great color & contrast, not a TN panel.
Another thing is response time, which to a lot of people is a big deal but pretty much a marketing gimmick because you'll be limited to what your latency online is anyways. If you need help buying a new monitor, let us know!