I guess I'm confused. The Razr comes with a small "external charger". What's wrong with that? And an external battery works because it will last for several days without having to be recharged itself. This means that you can still recharge your phone once a day (presumably as you normally do, while you sleep), and recharge the battery every two or the days, even while you're recharging your phone. Hell, as long as you charge your exteral battery every second day, you'll probably never have to put your phone on an outlet. This presumes if course that you can keep your phone on the external battery a lot of the time. I thought about getting the larger Anker, three 8000+ model, but it would be too big to carry around all day at work. The smaller one would be OK to keep the phone on much of the time in my pocket though. Hard to pay only around $10 less when the other has so much extra reserve, but there's a price to pay for portability, I suppose