Hi there Bebop - according to this site the SX5 model came out circa 1989.
http://www.geocities.com/vincentsxea3/EvolutionPart2.htm

I had a G7 which was an earlier model to this one (perhaps two years earlier) and the option with that model was what I think was called a RAM PACK, not a floppy disk. I don't recall having any problems accessing that and saving settings etc. so presumably there was some indication/instructions that indicated you were in that mode when you were using it.

As I said in my enquiry - it is no great loss if I never use the floppy feature, but, it like when someone asks a mountaineer why they climb mountains they will reply, "Because they are there!".....Joan