The energy is emitted as gravitational waves which is probably tricky to convert into usable energy and you probably can't attend more than one in your life unless you have faster-than-light travel. You're much better off visiting a supernova.
But in general it's better to have a steady and stable source of power, rather than one enormous burst of energy that you have to spend on something instantly.
But in general it's better to have a steady and stable source of power, rather than one enormous burst of energy that you have to spend on something instantly.