I had one but had to quit using it because the built in firewall couldn't be configured to let my Raspberry Pi based weather station get out to the Web. It seemed to work fine, as far as the mesh networking part of it went but my neighbors have come to rely on my weather station and I do too, so I switched to a different router that lets me out to the web.
Despite privacy concerns, the Google mesh system has no mic, so I'm at a loss to figure out how it would have any capabilities that any other router would have as far as listening.