My girlfriend wanted to get me a "unique" gift for my birthday a while back - so she got me one of those expensive gaming chairs - it was similar to the one in 40 Year Old Virgin. I used it once, said thanks but no thanks, and returned it with her.
The speakers by the headrest had poor fidelity. There was a sub in the seat cushion, along with a motor to vibrate. The sub was decently loud, but it's not for audiophiles. The vibration was alright, but there's no real logic involved - it simply outputs low frequency audio waves as vibrations. I tried it with Guitar Hero II (before III and Rock Band were out), and it was really off. It's just alright for shooters. I think it would really shine if you were into racing games - especially combined with a force-feedback wheel.
Though the chair had one big upside - it had a lot of storage space - drawer underneath to hold controllers, USB inputs to charge them, cup holders, etc. But really, I hated the fact that I had to plug the chair in and string up a bunch of wires to it.
If you're in the market for a seat to play games in, I'd look for something not targeted towards gamers - but more for comfort. Preferably something where no electricity is involved.
