Ya I six box "fine" with 9600 1/2 G also.

Thats not meaning that more video ram wont help.

If you read a lot of the hardware threads here you find that the number one bottleneck is moving infromation (textures) from hard drive to video card. Clearly the game dosnt really tax the cpu calculations or GPU calculations, its the moving of data. When you get more system ram you dont need to access the hard drive as much and that shows a LOT of improvement because hard drive access is very slow. If you have sufficient system ram then more video ram means that you dont need to move data from system ram to video ram as much. I mean that obvious, if the texture is already in the video ram you don't have to get it from the system ram. Now this impovement won't show up as MUCH of an increase as more system ram because access to system ram is WAY faster then access of hard drive. BUT thats not to say more video ram is "overkill".

More video ram is better BUT more system ram is better still.

Its completly not true that the fact your GPU is not at 100percent means that more video ram is not needed. The reason your GPU is not at 100percent is that it has no data in its ram to work on ... but ya even when the ram is full the GPU still dosnt go 100percent as the game just dosnt demand it.

And why do you think you run 60fps in middle of no place and 10fps it city. Cause you have to load tons of textures of other characters in cites, and none in middle of no place.