My only consideration now will be for a truly near mint nFD f/4. It's smaller, lighter, newer, use filter sizes that I already have and is IF. There are several on ebay including some supposed near mint and EXC+++ (whatever) examples but invariably they all have dust in the lens. How on Earth does dust get lodged inside the glass? I have four Fdn lenses that I bought brand new back in 1980 and now thirty-eight years later they are all as perfectly clear as the day I bought them with absolutely no dust or anything else untoward for that matter inside them. What does a person have to do in order to find what I want that looks like that?