Early in 2005, I bought a Sandisk SDMX-1 1GB USB memory stick and music player. Here are a few observations on its operation and usefulness from the perspective of a Linux user.
The first question of any piece of USB gear when it comes to Linux: Does it work? Yes, it works fine. I believe most anything that presents itself simply as a storage device works fine under Linux. All I do is plug it into a USB port, and the system detects it and sets up a mount point.
My OS of choice runs HAL, which uses the volume label to come up with the mount point name. Because the Sandisk ships with no volume label, you'll have to add one yourself if you want the automatic fstab entry to be something other than /media/NO_NAME. I used mtools to do this. Add the following line to /etc/mtools.conf:
drive f: file="/dev/sdb1"
The drive letter can be anything, you're only going to use this for two seconds. The /dev entry should be the one your USB drive shows up as (I already have an sda, so it shows up as sdb). Then do:
root@localhost# mlabel f:sandisk root@localhost# mlabel -s f: Volume label is SANDISK
Once mounted, it shows up simply as a 1GB FAT partition. Just copy music files into it; subdirectories can be made and used. It can store data just as well as music files. Software to manage what is on the stick is included, but I've never seen a need to use it.
Annoying quirk #1: Music files are played in directory order, not alphabetically. Just because you have an album ripped with numbered tracks, this may not be the order in which you hear them if the files were not created sequentially. If you copy a directory to the USB stick using `cp -r` or similar, the directory order may not end up matching what you'd want. Better to create a directory on the stick, then use a file-matching pattern like `cp directory/*.mp3 /media/SANDISK` to make sure things get copied over in the proper order.
Annoying quirk #2: After being shut off and turned back on, the volume always resets itself to 30.
Annoying quirk #3: This is probably by design, and quite possibly for a good reason, but when the stick is plugged into a USB port, it cannot be operated by its own controls. Maybe you'll never want to do this, but I kind of expected that it might be possible, at least when I was trying to figure out what order it was playing files.
Annoying quirk #4: Sometimes there are audible artifacts during playback of some MP3 files. To its credit, this was mostly when the MP3 files themselves were of questionable quality, and since updating the firmware, I don't think I've heard this happen.
Annoying quirk #5: The firmware itself is not crash-proof. I have gotten mine into a thoroughly confused state by going between various screens too quickly, requiring a power-cycle to clear. This is after updating to the latest version. Fortunately, it is a rare occurance.
Annoying quirk #6: The speed at which the display scrolls information seems to be either far too slow, or a little too fast.
The firmware is updated quite easily. Go to this page and follow the instructions. Mine came with version zero point ninety something, which upgraded successfully to 1.02, still current at the time of this article's composition.
The battery can indeed be removed and replaced without losing any data that is stored on the stick. You just can't play music in the meantime.
Battery time is not that bad. I use mine for about 30 minutes at a time during my work commute, so I'm not sure exactly how many hours a battery gets on average, but I go at least a couple of weeks between changes. The battery indicator on the front panel display seems a little flaky, though it's probably the battery itself that makes it seem that way. What I mean is that the display will get down to zero (blinking with no bars) and keep playing for awhile. On my next commute, it starts back up with two out of three bars lit. I simply wait until it shuts itself off with a low battery message before swapping it out; I keep a pack of AAA's in my car just for this.
It comes with a little clear plastic "cozy" that looks and feels a bit chintzy, but I always keep it on as it is pretty good at protecting the stick from getting all scratched up as it goes in and out of pockets, backpacks, laptop bags, etc. It also includes an armband to fasten it to your bicep and listen with headphones; I have never used it, so I can't report on how well it works. The headphones that come with it are not great, but if you're picky about that sort of thing, you'd probably want to buy headphones separately anyway.
In short: At $120, it's a pretty good deal. The media player is certainly decent. 1 gig is plenty of space, enough for me to keep a couple of "mix" directories for my commute, with room to spare for hauling around several albums' worth of files, or the occasional ISO image.