Pino Giaquinto:"It's not clear what is the right floppy type to use: it seems that 1.44MB FDD can also be used even with some compatibility issue (why?)... closing the second window of a 1.44MB floppy with Scotch tape and formatting it in the Plus D... shouldn't it work as a common DSDD 720KB? Why shouldn't it be reliable?"Enrico Maria Giordano:"Honestly, I don't remember if it is possible at all or reliable. I always used 720 KB floppies with my Plus D. Anyway, I presume that you will try it when you will get the interface. :-)"
I've tried the good old trick of covering the HD hole of 1.44MB floppy disks and then using them. The reliability of these disks used as 720KB disks varies greatly. I found some disks worked great for years, while others would fail at the formatting stage, yet format fine in 1.44MB format on a 1.44MB drive. I must admit I've only ever tried this using a 720KB drive on attached to the +D. You may have more success using a 1.44MB drive which has a READY signal.
LaesQ