I got this lens at Ebay USA for 500 USD !!!! The bargain of my life ! Before this one, I used the M 2.8/90, which is also excellent and a little bit more lightweight. I sold this lens after aquiring the Apo 2/90. This lens is simply outstanding. Crisp, sharp, bright and not too heavy.
Mechanics; perfect optics from f/2 on
None; The lens is worth every penny (according to the official price)