Typically the clear coat on a bass boat is meant to protect the metalflake. You can choose a clear paint or clear gelcoat.
Clear gelcoatis typically what bass boats use at the factory for UV protection over metalflake but gelcoat isn’t as easy to use as paint. Gelcoat typically covers 48 sq feet applied at 18 mils thick per gallon.
So paint vs. gelcoat, the thicker the coating the longer it takes for the sun to burn through. Time in the sun/elements is what will determine how long the clear coat lasts.
Use each product link for more information on price, application and coverage (tabs under picture for specs/how to use).