Any electric appliance will only take the amperage it can handle as long as the voltage is right.
My experience is that my Xperia V charges a little bit faster on 2A (2000mA) compared to 1,5A from the charger that Sony included.
I have never measured the max output of the Sony charger, but I find it rather small and light for a 1,5 model and it doesn't even heat up a lot so I doubt that it can deliver a steady 1,5A over an entire charge.
There is something you might pay attention to, certain chargers have a circuit that tries to recognise the device that is connected.
These circuits are not very intelligent, mostly it recognises if it is an apple or not.
The apples will get more A....
Simply using a "charge only" USB cable often helps to get the high A available for other devices.
This is often seen on external batteries, I'm not sure about aftermarket chargers, nor if Samsung chargers recognise Samsung phones.