Now it isn't uncommon knowledge that PSP chargers break easily. Bad wiring is usually to blame. This charger is my fourth over a long period of time and my second USB charge.
It works fine, seems durable the only issue is that the PSP needs to be switched off or in sleep mode whilst charging, which isn't suitable for hardcore gamers like myself. Luckily you can turn the PSP off at any point and when you switch it back on you will not have lost your progress, so it isn't too big of an issue. It is a pain to be sat waiting for it to charge with little else to do while you wait.
The USB feature is handy as there always seems to be a USB slot available, more so than free plugs so it is definitely worth investing in. The official Sony USB chargers will charge while the PSP is on, but are more expensive. If you don't mind waiting for a charge and want to save a few pounds then it is worth buying this charger.
Three stars overall, it is a good product but it isn't great.