Lots of other files and dirs on the card? Ooh I hope that's true. I'd love to carry a few radios around on a card with me to test when I end up in different areas. Flashing with other stuff on the card didn't mess up the rest of the files on the card or anything?
I haven't had any issues. Able to flash ROM's / Radio's on the fly
Also flashing from a MicroSD card is a lot safer than flashing from a PC