The motorola one you have is still a beast when it comes to recharging. I have a few of them, one in each car and an additional one for business trips. While running gps, streaming music, and the screen on, my battery still recharges. I have other 2.1 mAh chargers, but always come back to the motorola one. Especially since they are around $5 on amazon.
Sent from my gaming rig... which blows away my phone, but looks funny held up against my ear.