>Several points here. First, the screwmounts are a joy to use once you get >used to them. The loading is not nearly as bad as everyone says. Second, >the ergonomics of the screwmount are far better than the M series. They >are smaller and seem to fit in the hand much more comfortably. Third, as >for longevity, I believe that they are every bit as well built as the M >series if not better. My main camera is a Leica II from 1932, I had it >completely overhauled and it works like a charm. A mechanical jewel. >Fourth, lens. There are plenty of excellent lenses out there for the >screwmounts, both by Leica and from other manufacturers. Personally I have >an Elmar 50mm f3,5 uncoated, made in 1932, that just glows. In addition, I >have a Heliar 50mm f3,5 that is simply fantastic. An amazing unique >signature, loads of character (Pop. Photography ranked it as one of the >best three lens ever made). Leica even released screwmount versions of the >Summicron 50mm f2, Suimmilux 50mm f1,4 and Summicron 35mm f2 in 1999 on a >limited edition basis (2,000 in total I believe). Whilst not the cheapest >lenses out there, they are identical to the modern M glass. Here in Japan >I have seen the Summicron 50mm f2 for about US$900. There are also >excellent lens from Konica, especially the Hexanon 50mm f2,4. All >screwmount lens can be used on a M series camera, including any possible >new digital M, with the appropriate adapter which is relatively >inexpensive. Finally, a Leica IIIg is just so much cooler than an M3. >M's, and especially M3's are plentiful, a screwmount, particularly a IIIg >is a work of art in itself.