Well, my only Dahua cameras have been PTZs and all four of them had problems that would warrant new firmware. The first two were unable to take a 192.168.0.x IP address. I manged to get updated firmware on those, and and then the absolute positioning API, which I heavily rely on, wasn't reliable. Finally I got another round of updates which fixed them up and now they behave nicely. That round actually came from Dahua back when their tech support still provided firmware when you asked. My next two had other problems. One is terribly unresponsive while encoding 30fps video. I had to dial it back to 15 FPS to work around that. The other encodes video just slightly funky so that most players can only decode the i-frames if there is not a lot of motion in the scene. I've tried for over a year to find firmware for that one, but can't because it is a Chinese national secret or something.