It’s the only OS on my primary laptop and desktop machine now! Everything feels well-engineered and mostly very consistent. Compared to Linux and FreeBSD, stuff like suspend/resume, brightness/volume hotkeys, etc. not only work, but work on the console and with a plain window manager (no desktop environment). The classic example is how Wi-Fi, even autojoining (as of recently), works without the mess of ifconfig+wpa_supplicant+NetworkManager. OpenBSD’s ifconfig supports all this without wrappers upon wrappers.

It’s still a very niche market, though, so you have to stick to relatively well-tested technologies to avoid running into inconsistencies and issues.