1. Unpacked device - well protected device inside. Took 10" 2. Plug in power socket to wall, connect USB cable to charger. Took 5" 3. Put Nexus 5 phone on top - starts charging and appears to be charging rapidly. I tried my son's Nexus 4 and it also works.
Great little device - the micro USB socket on the Nexus and most phones is so small and it's easy to damage the socket by trying to insert the cable the wrong way round.
For people who say it charges slowly, think it's worth trying the difference between plugging the USB into the charger vs into your PC. Most PCs don't put out the same power as a mains charger...
About to buy a second one so I can have one at work too.