Quick charge is not by the Ampheres of output.
Thats what i just realise yesterday. Its the voltages that went up to 7.5V and 1.8A on my Note Edge. Thats the criteria for all Snapdragon CPU from 400 onwards will support fast charge 2.0.
7.5V*1.8A ~ 13.5W this is extremely fast charge.
Those power bricks like Anker or any other brands do not have Qualcomm certifications will only output high currents, but lesser volts.
Give you 1.8A * 5.2V ~ 9.36W at max. This is normal charge actually.
Heres a pic of Voltages from my note edge. However the Crystal non X cant utilize fast charge on Samsung charger and will max draw 1.35A * 5.3V ~ 7.1W.
I believe Softbank fast charge 2.0 charger will pull even higher wattage.