How effectively did this system perform? Since they are very limited in availability and very pricey, I assume they were not well accepted in the marketplace?
I have not shot a lot of rounds through my 547 but it works fine. I suspect most of these guns don't get shot a whole lot so I don't know how durable the system is.
SW supposedly designed these at the request of governments outside the U.S. (France and/or Israel according to good Internet hearsay). SW ended up with some extras which they sold in the U.S. The U.S. shooters asked, why a 9mm revolver when we have .38 specials and .357 magnums in the same frame size? So, S.W. never ended up making a lot of these guns (maybe 10,000 or so). Certainly not rare but not real common either.
I've also been waiting for the 9mm Pitbull. I think a 9mm revolver fills a nice little niche between the .38 spl +P and the .357 magnum if you only want to stick to factory loads.