My Galaxy S4 decided to melt its usb port in a car charger about a year ago. Since then, I've bought a couple of extra batteries (much cheaper than expected) and a couple of external chargers. Whenever I get around to upgrading and get a phone with a working charge port, I expect I'll continue my current practice. I'd much rather throw a spare battery that's little bigger than a credit card in my pocket than faff around with usb cabling or hope I make it through the day. Also the external chargers top a battery off much more quickly than charging through the USB ever did.
Have you considered getting a wireless charger attachment for your S4? That way you don't have to shut down your phone to fill up the battery, at least at home or in your car.
Haven't really thought about it. With the spare batteries at hand, it's only a few seconds to swap them. Have to be careful to shut it down completely before popping the old battery, or it will occasionally think the SD card needs reformatting.
