Really not much different than a household unit, just a different configuration of the parts to reside on the roof.
I would argue regular use is likely better than sitting for months before a hard 3-4 days then sitting for months.
Biggest issue I would see, is make sure you have good power supply. Low voltage is a common problem at RV parks and over time, that can burn out the unit. It's a gradual process so someone running on low voltage a few days per year may get away with many years before it fails. A full timer would rack up those days far more quickly.