I did some further research. On “anythingbutipod” forums, right after the m200 was introduced, some European users changed the firmware to American because the European version doesn’t have an FM radio. Looks like right after that, SanDisk changed the firmware so it trashes the unit if you try it. What you do is find the configuration file on the unit and edit it for a base firmware version, they run the update program.
I tried it. It trashed it! It worked great until I turned it off and now it will not turn back on. I removed the battery and pluged it into the PC and it said “unknown USB device” and still it doesn’t turn on. Luckily I used a 512 MB chip from a m230 with a broken display in a m240 so nothing is lost. I put the 1 GB chip back in and the unit works normally.
Circuit City has the m250 for $34.99 with free shipping online only. It’s $44.99 in the local store. And it has a one year warranty.
I looked at Ebay and the dealer said the unit had a 90 day warranty by SanDisk. SanDisk tech support says they DO NOT have warranties on used or refurbished units.