The MSI 6600GT is exactly $1 more than the eVGA one. Here are the differences:
MSI - OpenGL 1.5
eVGA - OpenGL 2.0
MSI - S-video cable
eVGA - none
The MSI also includes these games:
URU
XIII
Prince of Persia 3D
Splinter Cell
Deus EX: Invisible War
Praetorians
Commandos 3: Destination Berlin
Black Hawk Down
YAGER
Joint Operations: Typhoon Rising
Heaven & Hell
Comanche 4
Divine Divinity
American Conquest
Etherlords2
IL-2 Sturmovik
Beach Life
And this software:
MSI Media Deluxe Center II release 2
Virtual Drive 7 Professional Version
Restore It 3 Professional Version
MSI 5.1 Channel DVD Player
Foreign Language Learning Machine
Photoshop® Album SE
3D Album SE
MSI 3D Desktop
MSI developed software (10 programs)
Some of those games were very popular when they came out. I've never played any of them, so they will keep me busy for a while.
I think it's a pretty good deal, for $1 more and OpenGL 1.5 -- most of the other 6600GT's have 1.5.