Continuing the underwhelming theme is that screen, which isn't a patch on the Apple nano's smaller 2in, or the larger screen on the Sony NWZ-A829. Though videos play back at a smooth 30fps it seems darker and lacks the fullness of colour that those devices have. The usability of the device isn't that great either. It's not that the E100 is complicated to operate - far from it - it's just that it doesn't feel that responsive. Click one of the buttons on the front and there's a slight delay before the player responds. Try to scroll quickly down a list of tracks and it seems recalcitrant, sluggishly stuttering down, one track at a time - a far cry from the lightning quick track navigation of the Meizu MiniPlayer SL and Apple's iPod nano.
Fortunately, the E100 is pretty well endowed in other areas. Its music file format support is sound: on top of the usual WMA and MP3 support, you get support for the lossless FLAC format and Ogg as well. The device can be operated in MTP or mass storage mode, so you can drag music onto it as well as enjoying paid-for WMA files. The player sports a strong FM tuner, a 3.5mm line-in socket as well as an output for external microphone attachment, there's built-in mic for dictaphone-style recording and, finally, a microSD card slot for expanding the already-capacious 8GB of on-board memory.
Video file support seems pretty good too, with MPEG4, WMV 9 and AVI formats all supported. As with most pocket media players, however, you'll still find yourself having to transcode most clips you want to transfer. I dropped a number of standard definition MP4 and WMV files into the player from my collection of trailers and edited home movies without converting them first and it played none of them. Iriver does supply a pretty decent conversion tool for this purpose, however, for those who have the patience.