they sit around, fun if you enjoy them (as I did), boring if you want something active. Also quite a challenge to train to accept frozen food as they only eat live fish/shrimp.
I had a white and red wart skin angler. He like low flow and was super cool he ate guppys . I think if you like a fish that needs a lot of attention then its fine. but feeding it live food every few days was a pita.