I have a Motorola G2. It is an excellent general purpose phone.
The supplied charger is a Motorola 750ma output and Android estimates approx 1.3 hours to charge the device from flat. I have a genuine Motorola car charger with similar 750ma output.
I also have a Samsung charger with 2A output and Android estimates closer to 1 hour to full charge, and an aftermarket generic car charger giving a similar figure. That one is useful because it supports more than one device.
Are there good reasons the supplied chargers are lower output? Am I doing any damage or compromising the battery lifetime when I use the more powerful chargers?