"The XFX is undoubtedly the fastest of the five GeForce 7950 GX2's on test, but it is also the most expensive by a considerable margin - at over £527 including VAT, it represents very poor value for money, especially when you consider performance over a wide range of games. Indeed, there are occasions where its higher clock frequencies don't result in higher playable image quality settings. Of course, gameplay is slightly smoother and the performance gap will increase at higher resolutions. However, as we have already mentioned, we feel that gaming at 2560x1600 is limited to Quad SLI for the foreseeable future."
Read more over at Bit Tech.