The problems I had mostly to do with the way the player uses ID3 tags. You know, most music formats have information stored in them about the artist, album, song name, genre, etc. This is called the ID3 tag, and it's very handy for keeping your music collection organized. In fact, I spend countless hours using iTunes to prune my collection of 2,500 songs. I make sure everything is spelled and capitalized correctly, and that every track has the right information for genre, the album it came from, and the year it was recorded. I often attach the album cover art to the track as well. And iTunes does some really great stuff with all that information. I can tell it to play all my rock songs recorded between 1975 and 1983, and it will even add new tracks to that list dynamically when I import songs that fit the criteria.
So, the way the H120 handles ID3 tags really sucks. Since it's basically just a USB hard drive with no "syncing" software, you just drag a bunch of files onto the drive. Then you tell the player to do a "DB scan", which means it reads the ID3 tags of every track, and creates a database you can use to manage your music collection. In theory, it's cumbersome, but should be enough to get the job done.
The problem is, the H120 is terrible at reading ID3 tags. If your filename is more than 43 characters, it won't read it. If the filename has an unspecified "special" character in it, it won't read it. If iTunes has attached artwork to the file, it won't read it. Many files that looked like they followed all the rules were ignored. Now, there's nothing special about these files. Every player and tag editor on my computer could read them, but the H120 wouldn't. I found that if I used WinAmp to remove the ID3 tags, then re-create them, it would work fine. There's no way I'm going to do that for 2,500 files, and I really don't want to delete all the artwork attached to my collection either.
Now, if you got lucky and your files were scanned into the database, the next problem was it totally screwed up all the genre names. Some files were properly marked as "Alternative", but most were just filed under what looked like random numbers. "Yes, I'd like the '24' genre, please."
Okay, say you were really lucky and you managed to get your files read in the database with the correct genre info showing. Once you tell it to play all the music in a genre, it no longer lets you choose shuffle mode! It plays all the artists in that genre alphabetically. You have the same problem if you're playing any kind of list. It only shuffles within one folder (such as an album), or all files on the player. So if I tell it I want to hear just the Beatles, it's going to play every track in alphabetical order. Whee.
One thing I really love about iTunes is how easy it is to create playlists. The iRiver only lets you use WinAmp playlists, which are a little harder to set up, but not impossible. I didn't even get around to trying it, but I assume it wouldn't let me shuffle those either.
So, as much as I am in love with iTunes, I think I'd be much happier with an iPod. Right now most of my collection is MP3 128Kbps, because I had my car in mind when I created the files. But my new fancy headphones have made it a lot easier to tell the difference between MP3 and AAC encoded files, so I'm going to re-rip my music at AAC 192Kbps. Of course, only the iPod will play AAC files.
My disappointing iRiver H120 is already on a truck headed back to that evil, evil place from whence it came... um... Kentucky.