Zach,
That's a huge discount. The processors are pretty darn good now in the better sound cards, but you can end up paying as much as a mid priced receiver for one. I was just watching Toy Story II with THX on my 20" LCD running through my PowerSpec computer and Labtec flat panel speakers and a 5" sub. It doesn't compare to my Denon 3805 and Polk RTi10's/7.1 setup, but it's killer in the bedroom. When shopping for the smaller speaker setups, pay close attention to the tweeters. You'll notice the Altec Lansing and Klipsch have the best highs. The Polks will blow away the Logitech and Labtech speakers for highs, thus the reason they are more. I'd spend the extra cash and get the Polks. I think you'll be happier in the long run. It's only money, and you'll make plenty of that in your lifetime. Plus, with that discount, buy the best system you can. If you don't like it, you can always make a pretty penny on ebay!