The memory issues may be due to corrupt files, and not a player problem. I use a small plastic bag to prevent my Clip players from getting wet. Flash memory will wear out if you write to it too many times, although it seems like flash memory(even the least expensive of decent enough quality) should be good for at least 1,000 writes. I rarely change the music on my players though.
With Audiobooks, I writing 2 - 3 times per month (large files, though anywhere from 300 - 600 MB per book). It’s unlikely ot be corrupt files because I’ve alays been about to revert to the Clip+ with the same file and get good performance. While the + is a long term workhorse, I use it mostly as a backup.