Well, the exact numbers are mildly disputed as to breakout, but in mass market production terms of S&W revolvers these are small numbers.
I don't know that I would call them "rare" though . . . unless I was a gunshop trying to excite folks to buy using the old "Urgent Close."
THE ORIGINAL 400
Initially S&W produced and distributed 400 new Performance Center .40 S&W revolvers in 2001. Intended mainly for top revolver competitors (as well as folks who collect this type stuff) to be used as "race guns," they had titanium cylinders to reduce weight as well as the special tapered barrels now seen on the new 686SSR revolvers.
Here's the one that I owned back then, now retired and in the hands of a fine PC revolver collector on this forum:
These guns came with two different thicknesses of moon clips, to better mate it to various ammo being made that had different thickness rims out there.
Sadly, the rules makers of some of the key "gun games" changed the rules to keep this new wheelgun from dominating the field, so suddenly the "RARE" factor kicked in . . . for the competitive edge was lost.
Also, other complaints had risen by some shooters . . . of problems that some brands of spent cartridges being hard to eject, as well as some brands of cartridges flopping around in the moonclips due to non standardization of rim thicknesses causing problems.
Naturally, these early "problems" of using .40S&W ammo COULD have easily been solved, because this was the first time that auto cartridge had been used.
Alas, after this run of 400 revolvers, no further .40S&W production was ever made by S&W.
THE REST OF THE STORY . . .
However, Smith DID have cylinders already made for an additional 900 (or so) never made PC revolvers . . . and they soon used these, along with their L frame to use up those parts. Barrels of these non-PC versions were the good ol' "Plain Jane" full underlugged barrels of the 686 profile.
Once the unique .40S&W cylinders were used up (probably in 2002 or 2003 . . . hopefully someone with the details can chime in), no further S&W .40S&W revolvers have ever been made.
Members who have the later version seem to really like theirs too!
Hopefully one with post photos of their versions too for you.
WHICH VERSION DID YOU SEE, and what condition was it in and did it have it's original case and materials?
This would help better determine its value. Both versions are quite unique . . . and they ain't makin' either one anymore. Mine was HIGHLY accurate, and I've heard owners of the second version say the same about theirs.
Have a great Thanksgiving.