With HKSV, I rarely have more than a second or two lag. I have not tried the RTSP and probably won’t.
However, Apple’s AI still thinks my cat is a person and there’s no way to flag it for supervised learning. Facial recognition is ok but I have the camera pointed perpendicularly to the door so it usually only sees profile views. I’m sure it would work much better on a doorbell and I’ll probably migrate to Logitech for that.