I have looked at solar several times. I have a 1600ah battery bank and would like to put 4-6 340 watt panels on the roof. I have the real estate. Every time I work out a plan with panels, MPPT controllers, cabling, mounts, etc, the project is not too difficult. Then I try to figure out realistic usage - when we are docked at a marina, we are on shore power. On days we are traveling the two alternators can put 150-200 amps back into batteries each hour. The only days that solar would make sense are when we are on the anchor for days and the genset works day or night, sun or rain so the solar just seems like another complication on a boat where I try to simplify systems.
I wanted to install the most efficient panels I could find. I wanted to install SunPower panels but the dealers are not allowed to sell them retail. One dealer I found how had a way to sell SunPower, had them marked up 100%.