My home network is based on their networking gear but I stayed away from their camera system because it was too "walled in" for me (which feels weird to say as I am a heavy macOS/iOS user).
To me the biggest cons where that their very slick looking VMS software only works with their cameras, and their cameras only minimally work when used with other VMS (
Blue Iris, Synology Surveillance System, etc).. they'll provide a RTSP video feed, but AFAIK there's no way for the VMS to do normal ONVIF-related things like flip the camera between day/night mode etc. It also seemed like a very long time (over a year) after folks were running the great 5231s here before Unifi marketed their first low-light camera.
IMO, surveillance is not a major focus for Ubiquiti. As a hobbiist, with as slowly as new tech seems to come out in the surveillance market in general, I'd rather leave my options open to play with the new stuff that comes out from the manufacturers who focus on it (which for me is primarily Dahua, with some Hikvision) than lock myself into just one manufacturer's ecosystem.