Best USB cigarette lighter adapter for car?

[ItnStln]

No. The phone limits it.

--Tapatalk 2 on SGS3.

Any idea what the GS3 limits it to? It is my understanding that a dedicated charging cable will charge faster, is this incorrect as well?

 

[worwig]

Any idea what the GS3 limits it to? It is my understanding that a dedicated charging cable will charge faster, is this incorrect as well?

Yes, I have measured this a few times.
It is around 0.3 amp if it is attached to a USB port. It is around 0.8 amp when attached to a fast charger (data lines shorted). No point in getting a 5 amp charger.
Fast charging results from shorting the data lines. This can be done in the charger OR the cable. If you read a couple of posts up I tell how you can modify a charger to make it fast.
Those amperage number change a little based on the charge in the battery, quality of the wire, and the exact voltage from the charger. I bumped the voltage up on a charger I made for my motorcycle to about 5.2 volts. It can run the display at max while using the GPS and still charge the S3 fairly quickly. It is closer to 0.9 amp max. But attached to the handlebar, it gets plenty of cooling air on it so it is reasonably safe.
Figure the battery is getting roughly about 20% more current (due to the switching converters dropping the 5 volts to 4 volts) and you can see that a dead 2.1 amp S3 battery can take over 6 hours to charge from a USB port and over about 2 1/4 hours to charger from a charger with the data lines shorted.