Hi Weston,
Thanks for your comments.
In the meantime I had already jumped the gun and purchased a Sansa 280, which I am very happy with. However, all I have done with it so far is download an MP3 audio book and listen to FM radio.
I realise this device is not officially supported by MacOS, but at least Leopard doesn’t reject it. I was able to mount the Sansa 280 as a removable drive on the desk top, erase it with Disk Utility, and reformat it to MS-DOS (FAT32) without losing it’s database.
When mounted on the desktop it accepted drag-and-drop MP3 files with no problem and they play just as I intended.
I was concerned about not being able to update any firmware without resorting to downloading on a Windows machine, but according to the SanDisk website, a firmware update for the e250 is available as a MacOSX download. There does not yet appear to be an equivalent download for the e280. Perhaps later?
As I said, I have only mainly used the device for listening to an audio book, so I cannot discount possible future problems with some of the other features.
Why did I choose the Sansa over iPod? Dollar-for-dollar is seemed to offer more, and people on various audio book forums had expressed their satisfaction with it.