With the flip closed this is a tiny phone, just 104mm tall, 43mm wide and 11mm thick. It weighs a mere 75g, making it one of the lightest phones I've ever reviewed. If, like me, you are always on the look out for something that'll fit in a small pocket, then you could be drawn to the W350.
But hold your horses. As usual, Sony Ericsson has gone for its side-mounted headset connector; that enormous lump of plastic whose connector doubles up with the mains power charger. On a phone this size it looks stupidly large, and more importantly for music fans, turns a 43mm wide phone into one requiring closer to 60mm of pocket width. Unforgivable, really.
At least there is the saving grace that the headset is two-piece with a 3.5mm slot just past the microphone, but that won't help your pocket space any. Only the Bluetooth stereo output can do that.
While I'm on the subject of music playback, let's talk about battery life. Sony Ericsson quotes up to 7 hours of GSM talk, 300 hours on standby. My own music rundown test - seeing how long the phone can play tunes non stop off a full battery charge - delivered 11 hours 52 minutes of tunes, which is very respectable indeed.
Memory is important to music fans too. The W350 has just 14MB built in. The Memory Stick Micro slot you'll need to use to expand on this sits underneath the battery cover, and you don't need to remove the battery to get to it.
Music fans will appreciate the lock button on the top edge of the phone. This locks the front keys when the flip is up so you can't unintentionally punch a button. But it has no effect on the keys that are hidden by the flip. They work when you open the flip whether the hold button is activated or not.
When you are playing music with the flip closed, the music player occupies the main screen. With the hold feature on or off, opening the flip takes you out of the music player and into whatever app you were last using. Frequent texters will love this ability to flick easily from music to texting.
Oh, and one other music related point. The loudspeaker is really loud. Fellow public transport users might not appreciate this one bit, though I found it handy when listening to the phone's FM radio.