Welcome to the forums. The 2 tone on the delta is "Bear Coat" finished, satin black on slide and matt\satin sliver on frame and small parts (Les Baer use to do this on many of his builds). This is a very early 1st gen that is all steel, the stainless versions came many years later).

The delta elite is fine w/o the supported chamber, just watch what you feed it. I agree with what other have said, spend the 600 on another 10mm with the supported chamber. These are my two 10mm, the delta is a first gen that I bought new back in the day, and the kimber is my 10mm with the suported chamber. They both have quite a few mods done to ensure reliability and to enhance accuratcy, they shoot as good as they look.

The bar-sto barrel I bought right after I got the delta, just never installed it (it's still rocking the stock barrel.