Battery life, at least for video, is par for the course. The specifications claim around 4.5 hours for watching video and I couldn't find fault with that claim, though I'd have liked more than 13 hours for music playback.
Delve a little deeper, however, and cracks begin to appear. I'll address the screen first. It has a decent viewing angle and is plenty bright enough for shared viewing in a variety of circumstances – on a train, plane or on the back seat of the car – but it can't match the forthcoming Archos devices for resolution; 480 x 272 compared to 800 x 480 on the fifth-gen Archos players.
Neither is this a touch screen as the forthcoming Archos players are. And to compound this the Zen's controls are fiddly, with the familiar d-pad control too small for anyone with average-to-large-sized thumbs to operate comfortably. It's a shame because the navigation engine is actually quite intuitive and offers nifty features such as on-the-fly playlist creation for music, context sensitive menus that can be accessed with a single button click, plus the facility to browse by initial letter, which speeds up searches of long lists immensely.
We could forgive all of this if the Zen W's file format support was halfway decent, but unfortunately it isn't. On the video front we have support for WMV, MPEG 1/2/3/4-SP, XviD, Motion-JPEG and DivX. But alas there's only support here for versions 4 and 5 of DivX, despite the fact that version 6 has been out since the dawn of time. There's no VOB, MOV or native DVR-MS file support either. All of these must be converted using the supplied software – which can involve a tedious wait.
As a music player, the Zen W is a fine machine too, but is afflicted by the same problem as video playback. There's plenty of power on tap – enough to drive my Grado SR325i headphones to reasonably loud volume levels – and sound quality is excellent. But file format support is weak, with no support for AAC, Ogg Vorbis, or lossless file types such as FLAC, WMA and Apple Lossless. The Vision is restricted to just WMA, MP3 and WAV files.