As icing on the cake, the iRiver U10 supports MPEG-4 video, though as yet, there's no easy way to get this content à la iTunes. That is, you'll have to do your own video conversion on files that you'd like to play on the device. And while iRiver's user guide clearly documents the parameters for compatible video and describes how to transfer this video to the U10, it neither explains how to convert video, nor does the included iRiver Plus 2 software function as a video converter. Again, because of the relatively small 512MB or 1GB of storage, you won't be able to hold many movies, much less tons of audio, photo, and video files. A 2GB or 4GB version at reasonable prices would be preferable for carrying around such a variety of multimedia files.
Of course, the heart of an MP3 player is its digital music playback, and the iRiver U10 is no slouch in that area. The U10 supports MP3, OGG, and WMA files, including songs purchased from online stores such as MSN Music or downloaded as part of an on-the-go subscription service such as . You can transfer premade playlists to the device or choose from several on-the-fly options: make your own Quick List, or let the player decide based on Recently Played, My Favorites, or My Rating. You can also rate songs on the fly. For music playback, the U10 offers the standard shuffle and repeat settings, and you can also select from 13 EQ settings: Normal, Classic, Live, Pop, Rock, Jazz, Ubass, Metal, Dance, Party, Club, SRS WOW, and a user-defined mode. These EQ settings can be previewed in real time. What you don't get is autoplay; that is, when you turn the player off and then on again, it doesn't automatically resume playback. This can be quite a pain if you're not on the Now Playing screen when you shut down, since you have to navigate back to the song you were listening to. Oddly, though, once you get to that song, it will resume where it left off. Your videos will also pick up right where you left off.Thankfully, all the audio features don't go to waste, because the iRiver U10 sounds great and gets really loud. We preferred our custom EQ to the flat setting, but however you slice it, you get clear highs, a defined midrange, and tangible lows. But if you really want to experience all the U10 has to offer in the sound department (especially the bass), pair it with some high-end headphones; we prefer . The included earbuds sound surprisingly decent, but they're uncomfortable. The iRiver U10's rated 28-hour battery life is also good, but what's even better is that CNET Labs beat that time by more than 3 hours, squeezing out 31.5 hours of playtime (for music only). Transfer speeds were not as great, coming in at an average of 1.6MB per second.
Overall performance was similarly impressive in our real-world tests. The Flash games are surprisingly engaging and colorful, FM reception is excellent, and the related autoscan feature works well. Menu navigation is speedy, and you get accelerated scrolling through track lists, with a cool blurred text effect. Videos play after just a brief loading time (comparable to that of the iPod), and they look nice--though small--on the bright color screen. Unfortunately, there's no video-out option, but that's probably just as well since clips formatted for the U10's display would no doubt look subpar on a full-size screen.