The DB!C has been sitting on my desk getting a burn in test since yesterday afternoon. I have to say the video is amazingly clear, albeit a fisheye view. I took the trim off the front door, one side only, and pulled in an 18/2 and a CAT6. I'll probably put the DB1C up a little later this evening, at least with a temporary setup for the mechanical doorbell and transformer. I've got some AC wiring to do and that will be where the transformer will be powered.
I used the app, initially, to configure it but needed the Hik config tool to set the video, IP and so on. The response from a button press has been almost instantaneous on the phone, at least when I've fooled here in the house, so maybe I'll leave the app on my phone. BI found it, but I had to manually enter the video paths to get both the main and sub streams going. According to my router, it's connected at 6G.