I've not noticed a huge difference between the certified charger and regular chargers on my 1520 with the 8.1 DP. I'm guessing Denim will include the necessary driver tweaks for it to work. My Moto G (first Gen) does charge faster. For a certified charger, I recommend one released by pure.gear. They released one for the home and the car. The difference, also, is not in the amps pushed through the charger, but rather the voltage. Standard chargers push 5V whereas Quick Charge 2.0 chargers push 9V.