Just put a Fantastic vent in our LQ trailer, in the bathroom. It replaced the useless existing fan. The camper came with Maxx-Aire covers already installed, so I just used that with the F.V. A big improvement in moving air through the camper at night. It's a pocket door, so it stays open most of the time anyway.
With that success, I just bought a similar model for the TC, but will be installing it in place of the non-powered roof vent in the dining area, instead of the bathroom... didn't want to leave the bathroom door open at night. I just dropped the trim on the existing vent today (wanted to see how difficult it would be to run wires). I was surprised to see power wires already there in the box... on a 1995 model Lance!
If we get a couple of clear days, I'll be starting that project next. I did pop for the Fantastic Vent cover for this installation, to maximize whatever air flow is available. It is silly that these plastic vent covers cost this much. But, we have a trip planned with the TC in August, so I'm sure we will appreciate the benefits of the improved ventilation.