I have to agree with the Roccat assessment here. I've done a lot of research and reading about headsets and headphones. Chalenge is right, you can get a better performing set of headphones for 100$, but that still doesn't solve the Mic issue. The modmic is around 75$ delivered to me, so it's around 200$ for a decent lower end set of performance headphones with the mic.
For 100$, the Roccat is probably the best value out there IMO. I've handled and tried everything I can get my hands on, all the various Steel Series, the Corsairs (my fav company), Kingstons, Razers, and so on. Roccat has the best quality feel for the price, and the 5.1 issues like Karaya has said are a big factor IMO. I still really like the Sennheisers, but honestly, their lower end 350s are double the price of the Roccats. The 363 I really like, same as the Game Ones and Zeros, but they are closing in on 3x the price. For the money, I don't think the Kave 5.1 can be beaten right now. I ordered a couple sets of them for our various PCs in the home. I still went with a really high end option for my main gaming PC, the Beyerdymanics Gaming headset, but would never recommend them unless $ isn't an issue. Getting 3 sets of them = ridiculous, hence the Kave 5.1s from Roccat filling the bill. I still think the Psyko Carbons are/were the best for money no object range headset, but unfortunately like many great ideas and companies, stopped making them. Should anyone ever run across a set, please PM me, I'd love a shot at getting a set with the included booster/amp.