EpicMindWarp, The charger and the cables use two different protocols and you can't tell by reading the voltage/amp spec on the charger.
The USB connectors are standard four pin, two data and two power.
iPhone in their chargers have the device read the data pins.
Non iPhones use a charger only protocol from 2007 and 2009 (about) that shorts the two data pins in the charger.
Thus the device pulls amps based on the data pins being shorted.
All USBs devices connected to a PCs use the data pin protocol to limit the amps to protect the PC not the device.
Your idea about the after market or generic charger does not take into account which protocol they used.
Most went after the iPhone market and thus are short on amps. The device thinks its a PC outlet.
If the charger data says its for both iPhone and Non iPhone, it the iPhone protocol with the data pin will limit the amps. You'll be disappointed, I have several I played with.
iPhone makes a Charge Only cable to fool non iPhone chargers and you can get Charge Only cables with two wires to fool the non iPhone device as well. Better just to buy one that works the you don't have to label your cables.
Check the "do it yourself" fixes on the web. There are videos to show you how to cut the charger open and solder the data pins. Some go back years when the blackberry was having problems with the so called universal after market chargers.
Check the reviews on the chargers sold on Amazon. You'll see some feed back.
If you buy a single charger look for one not compatible with the iPhone.
It showed up in my LG Alley when the phone would loose charge while in use and plugged in to a after market chargers. I didn't care much because the screen was small and the Navigator wasn't as good as it is now.
The S3 is so much better at so many things people are starting use the Navigator, the phone, the music and notice more.
It needs 1.0 Amp not the PC or iPhone reduces amperage.
There are some dual car chargers with iPhone protocol on one side and non-iPhone on the other.
Here is one I found to work. The 1.0 Amp side works on the non-iPhone.
It's a GTMax Metalic Silver 2-Port USB Car Charger Adapter.
It will charge the phone while in use. I used it on a road trip today.
http://www.amazon.com/GTMax-Metalic-Silver-Charger-Adapter/dp/B005XRFRNU/ref=pd_cp_cps_1
There are others.
If you care it was while trying to find out why the generics I had did not work for my S3 I found
iPhone doesn't follow the:
September 2007 Open Mobile Terminal Platform,
the 17 February 2009 the GSM Association (GSMA) agreed standard charger for mobile phones,
the 22 April 2009 CTIA endorsed protocol, or
the Universal Charging Solution embraced by the International Telecommunication Union (ITU) On 22 October 2009.
And the generic don't tell you.
I know too much time on my hands.
So I did some testing... the original Samsung Charger charged my phone in about 3 hours from 10% charge.
An original BlackBerry charger also took the same time from 10%
An after market USB charger with cable took around 6 hours to charge from 15%!