Siberia v2 question

hey,
i heard that this gaming headset is really good and that it comes in 2 versions one with a usb that will support 7.1
and 1 without it so my question is will it be the same if i just have a mother board sound card that support 7.1 ?
and another one i thought of buying them online so i wanted to ask is this ones fake?
http://www.ebay.com/itm/2012-Brand-New-Steelseries-Sibe...
because he don't say so and i don't know if he allowed to lie or something and i need your opinion

that's all guys thanks