hey, basically want some feedback from those of you who have been there and done it.

Really, is the 8800GTX worth £100 ($200) more than the 8800GTS 640?

A little more info being, I'll be running at 1900x1200 res, playing games such as supreme commander, prey, quake 4, et quake wars when its released, stalker etc.

How much performance does the GTX offer over the GTS realistically?

Oh and also the GTX is an Inno3d version.

Thanks.