Ohh nice! looks like a 1993 S-Works Steel. they are a nice frame and for some MTB collectors they are a grail bike. rumored to be Tange Prestige Ultimate tubing. these frames are light. I have a funky setup 19" frame one , although its a little to small its a great frame

fwiw , they are not Stumpjumpers or any other model. S-Works was a separate line of bikes and they were all aluminum except this one. I would say they are rare , but since most dont care about MTB they are not overly expensive

heres my S-Works Steel (complete with Loooong steer tube..