Giant had dabbled with several other suspension designs before this, but this felt different. Like they were really taking it seriously. The thing was though, it was someone else's design.
In the late 90's, after Horst Leitner of AMP had really perfected his 'Horst Link' suspension design, Specialized bought it, and managed to get a patent on it. Leitner has said that he worked with Specialized in the early 90's, but they just 'screwed around,' so he started up his own operation.
The patent threw a wrench into the industry as Leitner had been licensing his design to several companies. They now had to pay the Specialized price. The issue was the pivot in the chainstay, which you can see in front of the derailleur in the picture above. Some just tweaked their designs, like Rocky Mountain, moving the pivot to the seatstay.
Some companies just bit the bullet - like Norco and Giant. The kicker though, was that companies licensing the Specialized FSR design had to put a Specialized sticker on their bikes. I found the one above on the NRS by accident. I don't think it's a coincidence at all that Giant put a black sticker on their black bike.
It does have adjustable rear suspension though. Two positions to mount the shock, giving either 3 or 3.5 inches of travel. This is laughable by today's standards of course. I've seen reviews in magazines where writers make fun of bikes with 4 inches of travel. It was pretty exotic, and worked very well from all accounts I've read. The Rock Shox SID shock is highly tuneable, and I believe Giant designed the bike specifically to take advantage of what the SID could do.
And finally, the reason I bought the bike - that mysterious unmarked rear derailleur. It is a Precision Billet Pro-Shift derailleur from the early/middle 90's. Several companies made rear derailleurs from CNC aluminium in this period, but I don't think any of them exist anymore except for Paul.
All of them were available in pretty/garish colours, all of them were very expensive, and none of them offered much of an improvement in shifting. But they looked great and showed that you had money.
It's a weird and very esoteric part that nobody will even notice, and it's exactly what I wanted. I'll put it on some old bike and we'll see if it's any good.
Anyway, the Giant is for sale. I think it's a perfectly good trail bike, and definitely better than any new bike that you can buy for the same money right now.