Could someone show me benchmarks so I can see which to order. :P
At comparable prices, you will get comparable performance.
Do not sweat minor differences.
For benchmarks, use google to find benchmarks using your cpu, games, and resolution.
And... benchmarks may still not tell all.
There is a growing interest in consistency of response times. Or lag as some call it.
It is an annoyance that is not detected on the average or even minimum fps statistics.
Here is one article about it comparing a GTX660ti and a 7950:http://techreport.com/review/23981/radeon-hd-7950-vs-geforce-gtx-660-ti-revisited
As to the amount of vram, I am thinking it is mostly marketing.
Here is one study comparing 2gb vs 4gb:http://www.pugetsystems.com/labs/articles/Video-Card-Performance-2GB-vs-4GB-Memory-154