I have a S2A (in fact, I have several of them I must admit), and find it to be a very usable camera. The viewfinder is not the brightest, and it's heavy and noisy, but it is very nice to use both hand held and on a tripod. The automatically returning mirror is very handy when shooting hand held.
And of course, the lenses are great, both the Nikkors and Zenzanons. And it looks good too.