There are many different topside boat paints and qualities, generally the more you spend the better the results.
Duralux High Gloss Marine Enamel is affordable and easy to apply and only recommended for above the waterline or moderate use on the bottom (a day or so in the water, not extended periods). This topside paint works best in very thin coats; see the prep recommendations found on product page on “how to use” tab. Duralux marine enamels does have a limited color offering in a flat finish, but those color choices are limited to their camouflage paint colors. For use on aluminum the Duralux Zinkromate Primer is recommended and for use on wood the Duralux Yacht Primer is recommended for best adhesion.
The best available boat paint for the topside with the best finish is Awlgrip, most expensive but best results and loved by customers. Awlgrip marine paint also requires a little more “do it yourself savy” to apply these paints, and require the correct activators and reducers when applying. The manufacturer of Awlgrip recommends it for above waterline use only.
Your topside boat paint choice depends on your budget, the durability needed and the amount of time you want to spend on your boat paint application.