I didn' t want to replace the roof vent on a new trailer either.
So I did the single speed Vortex fan upgrade and what an improvement. Real easy installation. It is a little noisy but it works 300% better. At the time there was no Vortex 2. Even at twice the price I think I would get the Vortex 2. Having a low/med/high would be nice and even though it is reversible, that would be a bonus but probably would not use.
http://www.campingworld.com/shopping...-upgrade/59009
Now I replaced my Maxx air vent cover with the newer high flow Maxx fanmate vent cover. Which is truely needed.
http://www.campingworld.com/shopping...ling-fan/49155
After all the installation, which was not hard at all. I turned the fan on and went to poke my head up to the roof. I could feel the breeze 8' away. Works like an attic fan for a house. Now taking a shower, there is no condensation anywhere. Very easy and happy camper, not a small fortune either.