I have dealt with them. It is a crapshoot. You'll either get a perfectly good pc or a piece of crap. Their customer service department is the worst I have ever dealt with, and their tech support is completely useless. If you don't know how to work on a PC, I would stay away from them. BTW, they also operate under the name of buyXG.com.
At the risk of being flamed (again) by JimJRJ, your sound issue depends by and large on what you are going to do with it. My experience has been that the newer on board sound cards are excellent quality. For my games, they work perfectly well, and if you are limited on funds, that is a good place to cut back, especially if it means that you can get a better cpu or video card(s). However, if you use your pc for music mixing or serious .mp3 work, then a sound card would more than likely be a good investment. I caution you, though : a $399.00 Creative Labs Audigy sound card sounds amazingly like a $16.00 I/O Magic card on $15.00 speakers

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As far as buying an high end gaming PC, try Widowpc.com. Their RR ratings are awesome, and I'll bet you can get a nice AMD based system for that $3000. (there are several listed in the $2500 range). GL and have fun shopping

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