Ah my mistake, it's a tough call: The SBZ may be the better choice since it does have some very cool features specific for gaming, and near the top of your budget. The E10k would be the way to go if your PC was your sole music source, listening to lossless FLAC and such, and is a bit easier on the wallet at $75.
Personally I am using a Samson SR850 with the Zalman lapel mic, connected to a Sound Blaster Play!3. It's perfect for my use - work, games, and the usual youtube here and there. The SBX surround I prefer for a large majority of all games I play, its very configurable and the SBZ has even more features. The casual music I listen to (mostly shoutcast streams) also sound excellent.