Summary: I bought mine for £2.49 "used like new" from an Amazon Marketplace seller. It didn't work, and I thought I'd got a dud. No instructions came with it, so I didn't realise it uses batteries until I read reviews here, and it took me a while to figure out how to open the device to put them in (twist the end without pulling it out). Now it's great. True the sound is not much louder than the phone on its own (using it on a Samsung Galaxy Y) but it is much better quality.
Summary: I purchased this lovely item as an external speaker for my Sony Ericsson phone not caring to have the mobile close to my brain for any more than short conversations. Works really well, but in addition, I have subsequently discovered that it also works with my little Ipod shuffle and as this is also brushed aluminium they look and sound fantastic together.
Summary: Got this for wife's Xperia X10 Mini Pro - perfect fit, amazing looks. It is true that the speaker itself doesn't add loudness, more like it deepens the sound. Listening to music with them makes a big difference - don't expect to have a party though!