It's pretty easy to hide a fire fighter somewhere in a house. With all of the smokes required by code, there's usually a spot where one additional thing on a ceiling is pretty benign.
We've never used one with nest, but we have used them with other hardwired and interconnected smokes... They've worked quite well.
I'm Not an engineer, but I play one on TV. My handle is Tweety but I have nothing to do with the organization of similar name. I just had a really big head as a child so folks called me tweety bird.
