I've put one in my new house. They are typically a whole home solution with the main part of the draw coming from the "wettest" part of the house. Bathrooms, fishrooms, etc. I have mine drawing from within my fish tank canopy and from my fishroom. It then deposits the fresh air about 10ft from my display in the center of the house. I have one with a variable fan that can run from 60cfm all the way to 150cfm. The higher the speed, the more likely that it's noisy. I ran extra large piping through the house to avoid the noise.

Dehumidistat and I have mine run 20 on / 40 off but I can also have it turn on manually if I need to (if we cook something stinky we can set an additional timer switch to 20, 40, or 60 minutes to destinkify the house). I have 4 vents come off mine, 2 of which service the tank room, 1 for the basement, and 1 that ties into the main furnace lines to service the whole house.

You could run it just to a tank room if you wanted but there are benefits to having the whole house serviced by it.

I also want to purchase a HRV. Does anyone know who sells/installs the Lifebreath make?