Ventilating shell with solar fan/vent-What about this product?

I am looking at the very pricey 4 inch Stainless Steel Day/Night Plus Vent Part # N20704S DAY/NIGHT PLUS 4" SS at http://www.marinco.com/en/n20704s
This is a unit for a yacht, and at the web page there is a detailed, 10 page installation guide PDF, but for mounting on a yacht deck.
Other products do not provide enough technical details, especially cubic feet per minute, etc. This one claims 1,000 cubic feet of air/hour. (= 16 CFM) It is self contained, running off its own solar power and charging its own small NiCad or NiMH battery for operation at night (thus the name "Day/Night"). Seems very well designed and highly engineered. Please, take a detailed look at the technical details at the web page.
ANYONE WITH ANY EXPERIENCE WITH THIS FAN INSTALLING IN A CAMPER SHELL?

 

No experience with a topper install, but installed a couple of these on my cruising sailboat. Yes, they are high quality. Built for the saltwater environment. I contacted Marinco and they sent me an extra set of fan blades to reverse the flow of the fan. I had one pulling air in and another to push air out.