I think when its in manual mode, you dont get access to the full range of brightness, only after putting it into autobrightness mode. Perhaps Samsungs way of not letting the phone get too hot and igniting like the Note 7?
The included cable charger that mine came with charges fast like that, I let it charge slow with standard USB port overnight, but the included charger nd included cable should achieve this. The cable is important.
Could it be that you're using the note2 during the in the winter and the gs3 summer that the gs3 appears to run hotter?
I run the GN2 in summer here and it does appear to be warming up a bit, more then I'd like it to be (it feels warm in the hand)
$43 for amazon for me
The manual states that 64gb is supported, so it shouldn't be surprising really that it works.
The internal chip is a bi faster writing at about 17mb/sec whereas the Sandisk writes at about 10. Plenty for media storage