To quote the AVGN: "Shoryuken? More like Shoryucan't."
I'd always hoped that at the very least someone would hack the ROM to make the special moves reliably doable and balance the damage. Not gonna hold my breath though.
Anyways, I remember playing it at the local Scandia after SF2 became a huge sensation. They got it only because of SF2 fever, and it was just a weird experience. It was the 6-button version, and did nothing but confuse all the other kids on why it played like crap.
It was the only time I've ever seen one in-person at any arcade in Vegas. Never saw the one with the pneumatic buttons, though I've always been curious to play it with those just to see what it's like.
Also, kudos Arcademan for that awesome technical info.