Sounds like a good move up in technology Ed. Dragging wires through a completed layout is a PITA.
I have a 16 camera hard wired system on my layout, and am using it much the way you are using yours, monitoring staging and other hidden areas. In my case, I'm going to stick with the hard wire. Lionel has made some camera cars that use the WiFi technology, and I'm not sure how many devices you can have active at once. I'll have to ask my son.
