@black_rectangle, -----> “The simple practical way is to use one mode. Your computer can’t see both”, but we have 2 different storages, the internal and external msd card, the internal use mtp while the external msd card use msc, so we must choose only one storage ?
While in MTP, both internal and µSD sotareges are seen by the computer as a single virtual storage. (humm, and what happens when you remove the µSD from the fuze, then?)
But in MSC, you see the fuze’s internal memory and the µSD as separate drives (which they are, of course). You have to choose between MTP (and wondering which files will die if you remove the µSD, until you do, and the files on the µSd will only be usable in that single fuze, not even in another fuze) or MSC, so you can control which files are in what drive, and you will be able to see the µSD files put that way in any other SD-enabled device. If you listen to DRM’ed files, you will have to stick to the allmighty fantabulous MTP.
And my personal taste: I don’t like things which do not work well in the operating systems I use everyday. I don’t like WMP (nor Windows, nor Microsoft products in general, as they show a very reasonable price/quality ratio [reasonable for them, no the customers]) and like to be able to use my fuze with any music player I want, or even be able to put music on it without a music player (I find the command-line and rsync much more efficient for that job, but I recognise I’m not the stereotype of user). I like to own all the data on my computer and devices. Thus, I don’t like DRM. I also like to be able to use the fuze as a expensive usb-key, and to share data with my friends between different computers. So, MTP isn’t even near to fit my needs, and I recommend MSC if someone asks to me, but I do not predicate in favour or against MTP: it just doesn’t seem to fit the needs of a lot of people. But it does for some. The rest is sansa’s lazyness and microsoft’s legendary product quality.
And no, I’m not a pro-linux-antimicrosoft fanatic. With that I mean that my opion towards microsoft does not come from the “microsoft is evil” dogma, too many frequent in the free software community, but from personal experience.