O da Apple fornece 10W. O genérico 5.9W, o que deixa o tempo de carga quase o dobro.
E pior, a segurança.
Pelas regras de segurança americanas, é preciso ter pelo menos 4mm entre os lados de alta e baixa tensão. No da Apple tem 5.6mm, no genérico 0.4mm.
Safety probably isn’t something you think about when you plug in your charger, but it’s important. Inside the charger is 170 volts or more with very little separating it from your iPad and you. If something goes wrong, the charger can burn up (below), injure you, or even kill you. Devices such as chargers have strict safety standards – if you get a charger from a reputable manufacturer. If you buy a cheap counterfeit charger, these safety standards are ignored. You can’t see the safety risks from the outside, but by taking the chargers apart, I can show you the dangers of the counterfeit. (traduzir)
via Ken Shirriff