There is no 'true' surround sound then it comes to headphones. It is simulated.
That said, it does come close to what a 7.1 sounds like, with a bit of hit and miss.

If you're buying a audiophile grade headset, I would suggest you drop by the Audiophile section of the forums.
For a gaming/audio set, you can give the Logitech G930 a try. It does simulate that 7.1 surround sound that you are looking for, it has an inbuilt mic and as an added bonus is wireless. As a gaming set, I would say the sound quality between wired and wireless is indistinguishable for the majority of gaming users.

The reviews on it are pretty good and it is available at lowyat.

Sorry, don't know where you can test it as all shops I know of have it boxed up.