Every state has height and number of forward beam restrictions (typically 4, including factory headlights, if they are on). Find out what yours are. Might even be brightness limitations too, nowadays. Know what the rules are before you break them or decide to disregard them.
Very true. Although if you stay reasonably close to the rules and use the lights properly, you can generally get away with lights that aren't strictly legal and not be bothered for it. Technically, anything over 55w is illegal in most places, as are ECE headlights (most don't meet DOT requirements and only Massachusetts explicitly allows ECE lights).
Then again, my low beams are 55w and the ECE lights look pretty much stock, so nobody has noticed or bothered me in the several years I've had them. And the 100w+ driving lights are only on with the high beams, so even though I'm running 4 compared to the stock headlights + 2 the law says I can run, it's never gotten me bothered (law only cares about how many are actually turned on, not the number present, so killing them with the high beams when there's cars around keeps from being bothered).