I needed a spare to use as I'm not always at my desk and this compatible charger does the job well. Its safe to use as the voltage is the same output but the higher Amperage means it charges very fast, Under 3 hours from flat roughly. So its worth the money in my view. Also it can be used for charging some Tablets as they require a higher Amp output.
Also the service from MobileFun has been excellent, arrived quickly and protected.