The power supply was already known to me, as it comes bundled with a Sony XPERIA X8 and had proven itself in the family and for charging an iPod Touch 3G. When I was looking for a cheap USB charger it was a) is by far the cheapest brand device that I could find (in the reviews several "Apple" devices was to read that it is in reality to no-name products from the Far East ) b) I was already known positive personal experience.
The device is working properly for half a year. We recommend.