The 960 is in a lower performance segment. The card was designed and built around 2gb of VRAM. It is a great 1080p card for most games, and you should be able to play with high settings. The 4gb variants were offered by partner brands because it was perceived that 2gb was "not enough for today's gaming." This is only true if you are an enthusiast gamer who likes to use a lot of visual filters, especially anti-aliasing, to improve visual quality. The primary advantage that the 4gb variant has is in SLI, and that point you might as well throw down the money for a 980.
The GTX 970 is (still) a great performance card. 1080p, even with filters, shouldn't be much of an issue. 3.5gb of VRAM is still a pretty respectable amount that will last a while.
However, if you are willing to throw down $300-$350 dollars for a good GPU, the R9 390 may be the superior choice for you. I say "may be" because you want to make sure that you have a decent PSU.
960 just seemed like it was for nvidiots who would buy it just regardless of the competition in the same price bracket (as current nvidia people tend to stay nvidia). Some current gameworks titles have the 960 performing on par with a gen 1 titan, which is pathetic as it shows nvidia arent really bothering to optimize drivers for pre maxwell cards anymore and are going overboard on their tesselate like crazy technique.
I would say grab a cheap 290 or 970, they are comparable with some games green team winning and some games red team winning in performance.
the 970 memory nonsense seems blown out of proportion, I have plenty of friends who own them and they all perform brilliantly.
i saw a bunch of people who bought the 390 (not pre-release review samples, but actually purchased them) it wouldn't work with the newest drivers, or the previous ones. 1 person actually sent his back, got a different brand (Msi to sapphire) and THAT ones still didn't work.
the 970 issue was some bad stuff, but not only is it still a solid card, it actually DOES have 4GB of vRAM. It is just the last 512MB is slower.
The biggest problem with the 960 is that Nvidia held off from releasing it for so long - the 970 and 980 were selling so well, that they had no incentive to. So when they finally got around to releasing it, it faced a ton of competition. Since it was also a "weaker" card, both in comparison with the previous two Maxwell chips, as well as the competition, it is often written off. However, it still is a good card that is stupid-power-efficient, and does carry newer technology support. That's enough to sway some people.
I agree with the memory issue. While it was stupid to Nvidia to overlook it, if it was, indeed, an overlook, it only made a difference for those trying to run an SLI setup with super high settings. It's still a great card, and has a couple years of good use out of it, yet.