With the Ultra-Breeze you have to scrape away the old caulk to get to the screws. You the remove a screw and re-use the hole. The MaxxAir requires drilling into the side of the vent in order to mount clips. To me the MaxxAir system seems like it would be easier to install. An added advantage is that you wouldn’t have to buy any Dicor to reseal the vent flange. I installed the MaxxAir II on our last trailer. The installation wasn’t bad, but I wasn’t happy that the vent lid was somewhat limited in how high it could be raised
Both the MaxxAir Fan Mate and the Ultra-Breeze are the same height (10-1/4”), though I suspect the Ultra-Breeze might allow the vent lid to open up more due to the shape.
I’m leaning towards the MaxxAir.
