I do not have the SD version, but I do have the USB version.
The only real benefit to these (that I can see) is being able to load ADF images off a virtual drive, thus negating the need to wrestle with your aging floppy drive and floppies. Some games may not be friendly with WHDLoad or your Computer for that matter, so this may be a solution there. Likewise it's great for system installs or floppy based installs like Brilliance, which is pretty much the only thing I use mine for. A reason I feel makes a device like this well justified.
If your goal is to back up floppies, another solution is on the way from a different source.
