I've had a few problems, though only long-term. The data seems to "bitrot" quicker, probably an alignment issues that would go otherwise un-noticed. But for transferring data from windows machines to my Amiga, it worked well. The quickest I've noticed any problems was a week, and that particular disk was subjected to environments most jungle animals would find too humid. Only real issue was formatting the disk to DD, PC-side you of course need to scotch-tape the second hole, and I've yet to find an XP install that can format it via the GUI. Plus I can never remember the command line for formatting a 720k.. (format /? is usually my first call to said command). Also, found CrossDOS can actually format 720k better than XP can. But for just temporary Amiga storage/transfers they work fine.
