The ass brigade swears by them for building good glutes.
They had a little resurgence in powerlifting, the main thing being teaching trainees glute activation. But they fell by the wayside after a while. I tried them for a goof years ago, and you definitely feel them in the glutes and other parts of the posterior chain, but I just don't like setting up the lift. It's like Zercher lifts and the like, is the juice worth the squeeze? For me, I feel GHR's and similar way more, and it's a quick, safe set up.