You nailed all the important points.
I want to know sure that Overdrive audiobooks will not work. With my old Sansa Clip I just moved the mp3 files to the audiobook folder and I could play them as lomg as I wanted, regrardless of the library due dates that would expire on the PC THAT I downloaded them on. The new models would be worth it for audiobooks, though sorry not to have borrowed Rhapsody tunes while on the go or lawnmowing.