I watched an Acorn demo in 1993 and wasn´t terribly impressed. Amiga was far ahead on the user-interface (e.g. It seemed that proportional fonts were a problem for some of the more popular Acorn software). And the idea that some of it really was written in Basic didn´t impress me either.
BBC BASIC is very powerful, and it can do inline assembler. You wouldn't know it was running interpreted BASIC unless you went poking about or somebody told you.
I also beg to differ on the user interface. Both AmigaOS and RISC OS are wonderful operating systems with good and bad points. If it was up to me I'd merge the good points of both into some crazy hybrid OS. The drag'n'drop and context menus of RISC OS are divine, as well as the select-adjust clicks.
