Has anyone tried the SanDisk Ultra 32 GB MicroSDHC C10/UHS1 Memory Card with the Fuze?

Yes, it works.

I dug out my old Fuze  (which has a failing headphone jack) and put the 32GB card in. Works fine. 3300 songs, and as far as I remember what’s on there they are all visible, but I may have missed a few.

As I said, if you have crammed it with a huge number of songs, some of them may not be visible.