They also have a nice (if messy) solution for multiple device management with an external box (TechnoTim had some good coverage on his channel/website[1]).
Most other Pi-based KVMs use PiKVM's software anyway, and I'm not sure if any directly support PiKVM upstream (they should, IMO).
The other class is the JetKVM and its derivatives (many forked JetKVM's snappier Go software), and that's another reason I've stuck with JetKVM itself. It seems to have a nice community around it for mounts in almost any situation, and hacks to get weird things working correctly with it. They're also going to have a PoE + full-size HDMI version soon, I think, with microSD for expanded ISO storage.