1000mA is not exactly twice as bright as 500mA, but close. Anything over 700mA(except xpg whites) will mainly just build more heat. The dimmable buck pucks have a pot on them to dim. The meanwell drivers (D series)require you to use a controller or build a vairable 1-10v circiut.(12v ps with resistor to drop to 10v,then a pot). Hope that helps some, if not ask away.