The iFlash High Output 4 USB Car Charger (Amazon) uses up to 2.1 AMPs to charge your devices. Some devices, such as iPads, require more power to charge (or they just charge extremely slowly). My old car charger was very low power, so even an iPhone would charge really slow. This charger charges all of my devices quickly and easily. The construction seems to be of good quality, and it has worked well singe I bought it.
There is a red LED on the inside that lights up when the unit is plugged in and being powered, this makes it easy to see where it is at night if your driving and trying to plug something in.
I would recommend this unit to a friend. 4/5 stars.