I have several old synths with DD drives, and I've been using HD floppies with them for ~30 years without any problem. Late HD floppies were crap (whatever the

I have several old synths with DD drives, and I've been using HD floppies with them for ~30 years without any problem. Late HD floppies were crap (whatever the mode), but old HD floppies formatted as DD back in the early 90s still work perfectly fine. I have several hundreds of these. Some having been used hundreds of times. Some I still use weekly.