I myself have the Gainward 7800 GS+ with 24pp and it rox... 10k in 3d05 and 5.5k in 3d06 with 24/7 settings. It's OC'd to 650 on the core and 1460 on the memory.
The GS+ is however hard to find, and I don't think it's available in the US alltogether.
However, don't despair... ATI has released the X1950 Pro AGP which equals GS+ specs. The X1950 is also cheaper and available anywhere.
Are you only looking at nVidia? The reason I ask, is that the X1950Pro for AGP is just starting to show up. This card represents the pinnacle of AGP performance, and should easily beat the cards mention in this post. I don't have any links, but it shouldn't be difficult to find.
the bfg 7600 is a very good card, I did the same thing that you are doing. Trying to keep from upgrading any time soon(as in new system). Playing ut2004 at full settings all the way. Great card, great price! Got my son an BFG 7800 a few months ago for his agp system, and that card rocks also. but is twice the price as an 7600! AGP is a dead end, but why pay sky-rocket prices for memory, waiting for mem to come down before upgrading. So to me its worth upgrading the AGP(even though some-one else will say that it is not). But in the mean time, these new system boards and the 8800 pci-e video cards will be upgraded and the kinks and bugs worked out, buy the time im willing to upgrade. And besides new games are not really taking advantage of the new systems yet. But will be soon!