You might want to pose this question to the floppy hardware gurus at
"Individual Computers."

They make a product called the "Catweasel" which reads all floppy formats
known to man. as such, they proabably have some experience with drives.

http://siliconsonic.de/contact/contact_e.htm

Or Tim Mann is also a floppy guru.
http://www.tim-mann.org/catweasel.html