Are we sure that it is not harmful to the battery to use the higher watt charger?
EricE
Yes, all of Apple's devices, from laptops to iPod Shuffles have been designed to only draw only as much power as they actually need. This has been the case for years. Another advantage is that all of Apples's devices can be charged from any power outlet in the world, all you need is an adapter to convert the prongs to fit the ones common in the country you are in.