I own two Sansa players including an e250 2GB and e260v2 4GB. I needed to update the firmware a few months back to get all the features to work right. Getting the flash in was not straight forward (I forget the details). I have not tried the micro-SD card since flashing the firmware. Moreover, I'm no expert on this. So, I don't know if any of that applies to you. Just a FWIW if you haven't updated the firmware.
Be that as it may, both work great and well worth the relatively low price I paid at the time. One in our ballroom connected to the sound system provides all the music there, the other for the exercise cycle (was for my wife's 12 year old car -- but the old car broke a few months back -- the new one has satellite radio and all the "period" music she needs).
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