The sound cards supports true 7.1 surround, not virtual like its competitors does. If you are buying this card and the expansion card for hopes of 7.1 surround for gaming you aren't going to get it.
That being said the card does support virtual surround. If you are buying this card for gaming with headphones or for headphone use or a stereo speaker setup the expansion card will not be needed.
The card is quite powerful and drives my Beyer dynamic dt770's with ease. The audio quality is great for high quality music files and the virtual surround capabilities are adequate.
Right now the software is horrible. It's the first version of it but it's a little clunky with the 7.1 card hooked up but seems to be better with only the single card installed. The creative sound blast software on the other hand started out horrible but now it's very good.
Comparing this card to the creative sound blaster ae5 it's not a huge upgrade for headphone usage. I think with software upgrades it may surpase it in feature but that won't be for a while. The virtual surround on the creative card I find to be much more accurate in direction. So for a gaming experience I think the new creative cards are still on top however the surround quality on the EVGA could be improved through software updates.
In summary the creative card is a very good deal right now with a software package that has already been very refined, and is clean and functional. The surround is better and everything works smoothly. This EVGA card has very clunky software that has a very basic and a not very visually appealing GUI. There still seems to be a few compatibility errors when the 7.1 expansion card is installed and the virtual surround isn't a whole lot better than stereo. If you are buying this package for gaming, headphone music and stereo speakers setup you absolutely don't need the expansion card. It's only for a dedicated full room 7.1 speaker setup. Save yourself a few bucks and only get the main card.