Hi!
I'm looking for a DAP to replace my old Nokia 5310. I had the Cowon iAudio 9 in mind, but I read in
a review that you can only make one "on the go" playlist with it. WTF? It has so many features and you can't make more than ONE playlist?

. Since the days of my rusty Sansa E250 that I've been looking for something that allows you to make multiple playlists on the device and save them. So far the only ones that can do that are cellphones. Why? I don't get it. I have hundreds of files and I'm always making playlists, so the only "on the go" kills me.
Well, I need these essential features on the DAP, any recommendation? I hope that at least one player out there fits my needs

1) As I said, be able to make multiple playlists on the device and save them.
2) It has to support Unicode characters, most especifcally Japanese, as most of my music has tags and filenames in Japanese. If possible, keeping the menus and interface in English, but if not, it isn't much problem.
3) Battery life: at least 30 hours. Better if it can be ~40.
4) Capacity: 16GB or 8GB with microSD expansion.
5) AAC support (but I think now every player supports it). FLAC would be nice but not required.
Thanks!

Edit:
I wanted to add something about playlists. In my Nokia 5310, when I put something to play, it creates a "Now playing" playlist automatically and plays the files based on that. For example, I open a 12 song album and put play on the first song. What the player does is create a playlist of those 12 songs and plays that. This way I can delete one song of that album, or add another and I'll be always modifying that playlist, which by the way, I can save it like a normal playlist with a name. I hope that what I've written is understandable ^^. All this whole playlist thing is VERY important to me, as my "music world" (to give it a name) is based around the "Now playing" and editing and creating playlists.
I really can't believe that a lousy cellphone like my Nokia 5310 could integrate this concept in it's player and a DEDICATED device for playing music couldn't. At least none that I could find. I mean, something that's a CELLPHONE has a better software than something specially CREATED to PLAY music.
Thanks again for reading!