No idea without knowing what you are working on and what kind of condition it is. Probably not best to lock yourself into 1 product line since there is so much variety in paints. The three polishes I find cover about 90% of what I run across are Meguiars M100 (heavy cutting), Optimum Hyper Polish (moderate cutting), and HD Polish (light cutting to finishing). But I also have HD Cut, Optimum Hyper Compound, Meguiars #105 and #205, 3M Utrafina and Clearkote Red Machine Glaze.
2006 Nissan Titan silver with minor swirls. A 2013 Subaru Impreza white with a Pearl Flake. Very little in the way of swirls. Finally 2000 Honda CR-V silver that is outside 24/7.
All of them get a Spring cleaning: clay, correction/polish, and sealant from Adam's. This year I will add deconing the paint with an iron removing product.
My go to compound and polish combo is M100 and M205. M100 is easy to work with. Really nice cutting ability, easy to wipe off, little dusting, and finishes nicely.
Also I keep in the arsenal of products M105, M101, D300, HD Cut, HD Polish, and CarPro Reflect.