My 25 Safari came with a solar panel when I purchased it, sorry I don't know the specs but there is a controller and a small panel on the roof. This is the first RV I have had with a solar panel.
It is very worthwhile. It keeps the battery charged. I am into my fourth year with agm batteries. I think part of the reason is that the solar charger takes such good care of my batteries.
In warm weather and full sun, I have enough power to boondock. The variable here is the furnace, the fan motor is a power hog. Little or no use of the furnace means the solar charger can carry the load.
Even in cooler wheather with some shade or partly cloudy conditions, I get enough solar charge to reduce the run time of the generator necessary to fully charge the batteries.
Last, The controller of the solar charger gives me a much better idea of the charge state of the batteries than does the stock charge indicator in my Airstream. If I am charging the stock charge indicator puts the batteries in the green. The solar controller tells me the battery volts and the degree of charge even when I am charging with shore power.