I installed Rockbox onto an old Clip V1, and my current Clip+ at the weekend. This is a great piece of work.
I’m having great fun at the moment, being able to speed up my audiobooks without pitch-shifting.
Couple of niggles: The Updater app won’t allow original firmware more recent than 01.02.09.
I also had a heart-stopping moment when the Clip+ crashed during a database update, and I couldn’t see a way to revive it for a while, and was convinced I’d bricked it (I was “bricking it” too). Holding the power button for a good 15-20s brought it back from the dead.
Also, I’m still looking for an easy shortcut back to the While Playing Screen.
The Sansa firmware uses the Home button to toggle betweem the menu and the playback screen, but in Rockbox it toggles between the main menu and the previous screen, so I have to move through the menu and select “Now Playing”.