I kind of like the tweakability that comes with Nvidia's driver and the tool Nvidia Inspector, but it's severely limited on DX10 and higher as these game engines work a bit differently compared to their DX9 and earlier counterparts. There's still no anti aliasing compatibility bit for Elite Dangerous, for example.
For ATI cards there was RadeonPro, but the guy who programmed it abandoned his project when he went working for Raptr. As far as I know there are no more tweak tools for Radeon cards.
If you don't do much driver level tweaking you can get whatever you want.
In regard to AMD's upcoming Polaris driven graphics cards the company released this statement two days ago:
https://www.amd.com/en-us/press-releases/Pages/radeon-rx-480-2016may31.aspx
Rumor has it the new cards will perform in the 980Ti range (I believe that when I see it), but at a very low price point. $199 for the 4GB version of the card (and another 50 bucks for the 8GB version, iirc).
There's something else though that is of some concern to me. Usually games run fine on both AMD and Nvidia cards, however when there is the occasional misbehavior, it seems it takes AMD longer to fix it. High profile games get fixed in no time by both manufacturers if need be. It's the less popular games like Elite that seem to be treated as orphans by AMD.