I just have to know...what is the attraction of any used military firearm or uppers? I have seen first hand how these things get treated (over cleaned, abused, etc). I can only hope these are not operationally used examples. The carry handle uppers are classics, with the US M16A2 windage and elevation adjustable rear sight being the best one in my opinion.
What's the appeal? It's one of the rarest configurations on the civie market so that appeals to collectors. Others may want the same rifle they carried while they served.
As for abused and over cleaned? I don't mind some external abuse. It's mostly cosmetic. Parts are replaced as required so I have no issue or concern in using a surplus upper. Hell, a lot of people on this site put more rounds down the bore annually than the CF does. Does that mean I'm taking my chances by buying off the EE?