The Clip+ has many more important features than the Clip Sport. For example, the Clip+ combines internal memory with card memory, so you can have playlists containing songs from both. The Clip Sport has a song limit of around 2,000 for card memory, and around 2,000 for internal memory.On the Clip Sport, a playlist will work only with files on card memory or on internal memory, but not both.
The Clip+ has a song limit of around 8,000 songs. Imo though the most important feature that the Clip+ has is that it supports Rockbox. Rockbox is a free alternative firmware(operating system) for the player that offers a large number a features. For example, with Rockbox the song limit is probably extremely high, as no one has reported reaching it. Some use a 64GB micro SDXC card in a Rockboxed Clip+(formatted as FAT32). I like the crossfeed feature in Rockbox, which makes headphone listening much more like listening to speakers(it mixes part of the opposite channel into each ear with a slight delay. This effect is adjustable, or can be turned off). Rockbox offers great flexibility for playlists.
The Clip+ doesn’t display album art though, while the Clip Sport does. The Clip+ supports protected WMA files, while the only protected files supported on the Clip Sport are those from Audible. Putting Rockbox on the Clip+ might impair its ability to play protected files. Rockbox itself doesn’t play protected files, however Rockbox is a dual boot operating system, so a Clip+ with Rockbox installed might still be able to play some protected files when it is booted up using the Sandisk firmware.
The Clip Sport has a much larger screen than the Clip+, and battery life for the Clip Sport is listed as 25 hours vs just 15 hours for the Clip+ or Clip Zip. The bottom line is that if you want to use Rockbox or protected WMA files you need the Clip+(or Clip Zip). If you have a large music collection(more than around 2,000 songs) a Clip+ (or Clip Zip) would be much better than the Clip Sport, especially if you put Rockbox on the Clip+ or Clip Zip. There is no Rockbox for the Clip Sport, and it looks like Rockbox might never be available for the Clip Sport.
The song limits I mentioned are approximate as what is limited is the size of the database table, so having a complex file structure, or long file names or long tags might makes the limits quite a bit lower.
I have all thee players, the Clip+(Rockboxed), the Clip Zip(Rockboxed) and the Clip Sport. My favorite of the three is the Rockboxed Clip Zip, as it has all the functionality of the Rockboxed Clip+, and a larger screen, as well as the capability to display album art. The Clip+ can’t display album art. Due to the larger screen, when viewing lists, the Rockboxed Clip Zip displays more items at a time than the Rockboxed Clip+.
