"we all have our preferences of course but I don't mind the halfway house because it is more true. People do actually speak like that! There are a great many English incomers in Scotland who retain the English accent but start using Scots words."

Indeed, and I occasionally do so myself, having stayed (not, of course, "lived") in Scotland for a while in my younger days. But I see no sense in singing "toon" instead of "town" when otherwise singing in an English accent. That's not a different word, just the Scots version of the same word. I can imagine an English incomer in Scotland perhaps using "frae" instead of "from" or "wi'" instead of "with" if speaking a whole phrase in Scots, but not in a sentence otherwise purely in English.

Richard