We don't know what the future will bring us and what will be required. It doesn't matter which card you have, it might be not enough 4 years later. So, don't waste your money now, if you don't need it. Why not spending so much money today, so that your needs will fulfill and do this next time again. You could even SLI same card for a fraction of the price now.
I have looked at the NVidia cards & it seems all but the higher priced cards do not have enough V-Ram to create full res at 1080p
If you are looking PS4 equivalent graphics card, then even the GTX 750 Ti is enough. And it comes with 2 GB VRAM. Who is telling you, that this wouldn't be enough for 1080p or beating PS4? A GTX 950 would be enough, if you want it better, nothing more than GTX 970 is needed.
The PS4 graphic chip is equivalent to a HD7870, darn it because I sold my HD7870 over a year ago, now regretting it...
PassMark - Video Card Performance Comparison
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http://is.gd/n7wDjV
You see? You don't need the newest and most expensive card.