Originally posted by Not a Number As the saying goes nobody made a bad macro prime lens.
+1 If you are trying to pick one 100mm macro from another you are splitting hairs. You are not going to see any real difference in the real world. Go by features and price. Any of the Pentax 100mm are superb I have had 4 different ones and honestly cannot tell one photo from another. Obviously one with 'A' contacts is easier to use. However, I have seen older Pentax-A and Pentax-M lenses go for almost as much as brand new DFA 100mm ones. So shop carefully and understand that scarcity is altering the price more than quality in some of these.