Maybe I am getting old, but I don't like to lug big heavy lenses for shooting anymore. This Carl Zeiss Jena Sonnar 200mm f2.8 is huge compared to a modern Canon AF version, and at almost twice the weight. Strangely, it balances much better on the bigger Canon bodies than the NEX camera. I even get reasonably good in-focus ratio using the optical viewfinder to focus.
As I wrote before, this lens is best used on large sensor cameras, or on low density sensors. The 5D II is a good match for lens. If you need a long lens that gives you thin depth of field, and works on pretty much most camera systems, this one is a good choice, and it's quite a commonly available lens too.
All pictures below were taken with the Carl Zeiss Jena Sonnar 200mm f2.8 on Canon 5D Mark II.