No, I am not saying to buy a 970, but a 960 would not be a bad idea. I have no problems playing current games maxed out on mine, though I have not tried The Witcher 3 yet I can see here:
http://www.techspot.com/review/1006-...rks/page2.html
that with my 960 I could play on Medium settings and stay over 30 FPS, which his 660 could not do. If he's not looking to spend over $300 dollars and is on a tight budget, the 960 is still a good choice. Yeah, if your price range is in the $300-400 range, you'd be stupid to buy a 970, but if your price range is sub-$200 then there is no point in waiting for the 1070 and the 1060 is likely still pretty far out.