I had a chance to shoot one of these a few days ago
It's a six-shot revolver for the .45acp cartridge, using moon clips. This model has some variations from the standard; from the S&W website:
• “Miculek Style” .265” Wide Grooved Speed Trigger
• “Jerry Miculek” Wood Grip
• Gold Bead Patridge Front Sight on an Interchangeable Base
• Low Reflection Bead Blast Finish
• Designed in Collaboration with Jerry Miculek
The owner had replaced the grip with a Pachmayr, because 'That grip may suit Miculek, but my hands hate it'.
How'd it shoot? Very well. Very smooth action, clean trigger, and that bead front sight worked. I was only able to put about 50 rounds through it, which was enough to make me decide I want one(note to self, I really need to find that winning lottery ticket). I checked around, and finding moon clips for one isn't a problem, and they should last forever. Loading them isn't bad, but I'm told unloading them, unless you have a tool for it(like this or this), is a PITA.
Shoot well, and Earl Harbinger* carries one; why wouldn't I want one?
Now I've got to go out and mow some places before it hits 'melt you in the yard' temperatures.
*See 'Monster Hunter International'