GTX 660 Ti is good. 7950 is a little faster but Doesn't Physx.
7870 is faster than 660. But I have GTX 660 instead of 7870.
So, if you ask me I'd prefer GTX 660 Ti.
Its faster and enough for all those games. Even at 1920x1080 Resolution.
Check out the review http://www.techspot.com/review/603-best-graphics-cards/