I asked you want settings you aim for when running a game b/c it could be important - could swing which card you might want to go for next.
Nope - there never was and never will be really any need to spend $400+ on release of a higher-end card, when you can often go for a $200-300 mid-range card and be set for quite a while. Often, the bang-for-buck ratio goes way down, when you decide to bet the farm on a card and go for a higher-end one. And who knows how much can change, in a few years - namely architecture-wise, model-wise, generation-wise & card-wise.
Let's see - in May 2011, I bought a 1 GB 560 Ti (around $210, IIRC) when building that PC; & now in July 2015 have upgraded to a 4 GB 960 in 2015 ($204).
If I wanted a 4GB in 2011 - well, the Radeon HD 6990 was around $729. Too rich for my blood, to spend all on one part all at once here. Not worth it, IMHO. I'm not a millionaire.
I do think normally mid-range cards (i.e. $200-$300) when upgrading do hit that sweet spot of the worthwhile bang-for-buck factor - especially if you are someone like myself who constantly likes to tweak the in-game settings; video-card software's settings; runs gaming app's to monitor game performance + control it if necessary - all to get every possible frame & detailed pixel they can out of their card to find something they're happy with.
EDIT:
I don't think 2GB 960 ever really belonged in the mid-range pricing for $200, when it came out - should've been a 3GB, at that price. This is especially given how VRAM hungry these new games were when it came out + especially now w/ some of the newer ones. I think the 4GB 960 solves that VRAM hungry problem & is worth the few extra bucks when it's on sale, though (in the $220 or less range).