surround sound headphones

I'm going to a gaming con soon and I'm looking into surround sound headphones. are they worth paying for? I've found many sites saying that they should just be put together:

http://gizmodo.com/gadgets/diy/make-surround-sound-earphones-for-a-song-331326.php

what do you guys use?

IMO, not worth it. Just route the audio signal through a reverb filter and you can get a pretty good room-like effect for headphones.

Yeah, the XFi cards are pretty impressive with making 3D sound on Stereo headphones. I played STALKER that way and was even able to figure out where the enemies came from.
Normally the ear can determine the front/back thingy through its shape and how the sound waves hit them. And that can be simulated. Even Pink Floyd did things like that decades ago.