I just installed my CAMCO RV vent cover. Easy to install. looks nice. Cheap price.
However, IT DOES NOT WORK......... 20mins after installing (2), a moderate rain came with slight <5 degrees angle to the roof. The rain rebounding from the rubber roof allowed small amounts however noticeable amounts of droplets to enter the cabin.
I could tell while installing these Camco vent covers that the fixed louvers were not going to stop the rebound. They stop the direct rain but not the rebound or maybe sideways wind.
This is a terrible product. It does not work when you need it most.
The installation is not the issue. I pulled them forward and one to the rear of the TT vent. It just simply will not work in mod-heavy rain.
The Max ones may have more promise, they look bigger, which would distance the louvers from the vent. Not sure about the design. They look like they would have better air flow as well.