It's a delight to use, if a little esoteric at first. After the experiment phase, the software ecosystem comes up fairly limited. But I recommend visiting.
I briefly emulated it with UTM (QEMU) on macOS; the host was an M1 series chip. This story is the first indication that I might run Haiku on that machine's bare metal someday.
The window manager might look a little old-fashioned, but it seems solid as a dev workstation.