Reactor 3 is supposed to come with a resistor on the tail. You said you don't have it, then i assume that you either short the resistor or use a different tailcap. I have a badboy 400 and a shorted reactor3. My BB is greener than the reactor and dimmer also. However, the BB was properly heatsinked to the flashlight while reactor is not (as the head is plastic); therefore, it is highly not recommended to run reactor3 w/o the resistor for a long period of time. But i don't know how it is compared with BB500.