Well, not good...

Basically, if you set to read/write and exit, you will mark the filesystems as dirty and force and fsck. Highly annoying.

While it may not be the right way to do it, I have gone to shell, rwm'ed the music partitions, deleted the database files and run the player app from command line. I have not had it fail on me with either Mark2 or Mark2a players. Granted, if you have additional software in the background, it might cause memory problems.

One trivia note - when you q out of the player application run from command line, it is very graceful and sets the filesystems back to read only. So, if you were planning on doing additional work, you need to rwm them again...

Edit: I do this all the time keeping the players in sync with rsync. After the rsync completes, I used to run the player app while read/write, quit out, set the filesystems read/write again and then run swapon and mirrordb (symlink tree builder). Now, though, I am too lazy and just rsync the database files too...