I have been led to believe there are at least 1,000 possibly 1,500 S2s in the USA and the USA is about 20% of the global sales, so at least 5,000 S2s are out there in the world. I use one. I bought mine from David Farkas who is the S2 expert dealer in the US, and I suspect he might be willing to loan you one to try for yourself. I have personally shot at one time or another with 9 other S2 owners, so we are not all that rare, we just don't post much here. I guess that means I have worked with at least 1% of the owners in the US, and can assure you they are pleased with the system. One S2 owner lived 30 miles away before he moved to the other side of the globe.
I suspect S2s won't be on eBay much.
S2s are selling like crazy in China, where there isn't much of an issue with MF lens legacy. They don't post here either.
Many NYC pros are still renting S2 camera instead of buying, as they can just charge off the rental to the client. I know the big love of the fashion pros is a single modern S2 battery lasts forever, ( I get 800 shots per battery) and there is no need of a MF technician standing by for repairs. Looking through the viewfinder is a pleasure. No, the auto focus is not as fast as a sports oriented 35mm digital pro camera, but what MF camera is? The auto focus speed has not been an issue for my shots.
The S2 lens adaptor has helped some with both legacy issues and lack of every desired focus length available to date. The CS delay doesn't seem to be slowing sales although there will be pros who will wait for it. I have a S 120CS on order but using a regular 120mm in the meantime.
The worry about Leica dropping the S is limited. The company is making more profit than any time in it's history and is essentially privately owned by a German billionaire who had the desire to create a hell of a camera system from scratch. Sorry about the end of the R system, but when Canon went to the EOS mount they dropped many more photographers and Canon seems in hindsight to have made the right move. And what other company has had a mount for over 60 years like the M series?
If you want to see an example of how the S2 is to shoot, and users thoughts, go to the reddotforum.com
That is really the only site that a lot of users post on.
Try this link
http://www.reddotforum.com/showthread.php/435-Omo-valley-ethiopia?p=1764#post1764to see some very nice work.