Personally, and this is just IMO, I haven't seen a whit of difference in Aces High with Gsync enabled, from it being disabled. I've had Gsync since it came out, a while now, 4 different monitors from 1440p 144hz to 4k 28" to 34" 100hz 1440p. Gsync should not be one of your primary deciding factors, IF, and I stress this point, if Aces High is the only game you really play.
If however you play other stuff, particularly shooters or games like Witcher3 and that sort of thing, then yes, Gsync is a consideration, but still not the most important. You'll get far more out of a 144hz monitor over a 60hz than you will with just Gsync for your money. IE the 24" Asus 240$ 144hz monitor if you're on a budget is better money spent than stretching for a Gsync capable panel.
So far as the vid card, I can't stress this part enough - wait another couple weeks. The new 1080 nVidia cards will be out at the end of the month, and then the market for 980/ti/970/etc is going to be great for a used buyer. It's already showing signs of being great, good used deals all over on the boards I frequent, but the prices will fall dramatically even from that once the 1080s are in stock. Also, considering the 1070 new card will outrun a current Titan, the fastest card available now, for 379$, advice for the OP is - for the love of god, wait until it comes out, and buy that instead of a 650%+ 980ti right now, if you want a new card.
If money is truly not an issue, IMO going with one of the following for Aces High would be great -
-nVidia with the new cards/drivers had really improved 3 screen surround graphics apparently. So, going with 3 Asus 24" 144hz, or 3 of the cheaper ROG Swift 27" 144hz Gsyncs, would be amazing with a new 1080 card.
or
- I just got the new 34" Asus ROG 100hz Gsync, mrs is using it, but IMO it's better than surround with the curved screen and such, great IPS panel.
For vid cards - either wait for a great deal on a used 980ti. By great deal, I mean less than the price of a new 1070, ie less than 400$, as the 1070 will be faster than a 980ti, so no sense in spending more on less now. 980ti owners like me have had their cards rendered obsolete and their value hammered, but thems the breaks. If you can't get a 980ti for around 300$ish (IMO), get a 1070 in a few weeks, or a 1080 in a couple weeks (it's out first).
