660 Ti is a great performancy/money card. It generally rewards high FPS in games. I'd not advice to get a GTX 650 Ti though. Becouse of, in your case has very little CUDA cores, and has generally really low FPS in games.
The PB 278Q has higher quality and more screen real estate. While the VG278HE has a lower response time and double the refresh rate of the PB. It all comes down to personal preferance. More real estate, and better colors. Or higher response time and refresh rate for i.e. 3D.
Our lord and saviour Linus did a video on both:
And our one and only TTL did a video on the PB:
http://www.youtube.com/watch?v=fbGhz01JL24
If you really worry about monitor response time, consider getting a really high refresh rate monitor.
The VG278HE from Asus is a great example. Very low response time, and a really high refresh rate.