Normally it has around 40gb in ~210 folders. Because of the difficulties described in the x3 thread I filled it up to just shy of 59gb with music I don't normally keep on the card in roughly 275 folders. Sorry but I don't know how many files there are but it's about 85% 16/44.1 flac rips with the rest being mp3. The folder tiers are 2-4 deep.
The x3 took a few seconds to update when I put it back in and the first song did not play for about 5 seconds. After that it behaved as it had before, with no problems except for an occasional song that gets stuck. Meaning that pressing the pause/play button does not make it play, I have to back out to the folder level then select the song again. Not sure what triggers it but it's happened maybe 3 times but re-selecting the track works.