Can you use both ir and black Flash on dual flash modelsi dont think its enough to be overly concerned about it, the patented capacitor feature saves on battery usage and also insures you get a full flash regardless of battery level. There are more Leds on the powerhouse compared to the dual flash since you pick either black or IR on that model, There are other factors that will have a greater effect on battery usage than the flash module in the g/K series camera.