sth is being modest about what he's selling. Ideally you'd mount it somewhat centrally on the ceiling to get good coverage. I haven't yet installed mine centrally in my 2300sqft place but below is what I get with my cell phone on the opposite side of the house. Note this is also through the garage and the solar inverter/breaker panel. I don't have more walls or obstacles to get behind in this position. I'm in a neighborhood with lots of 5ghz but i am alone in my channel space.
My connection does 300/12 wired FYI
Imgur
My connection does 300/12 wired FYI
Imgur