I have a EGO-T with a Kanger ProTank. Is the occasional burnt taste from not waiting long enough between vapes? Or the Coil getting too hot? Also would like advice on what VV battery would be good to go with my ProTank. The ego-T 650mah batteries I have seem to not be putting out as much vapor as they once were. The heads aren't dirty either on the ProTank, I can put a brand new one in and not get the same amount of vapor, and still occasionally get a burnt taste.