If you are serious about sim racing, buying the Ultimate Edition is the only logical choice. It is frequently on sale for a fraction of the price of a single AAA title. Buying the packs individually usually costs significantly more than buying the bundle. If you already own the base game, you can purchase the "Season Pass" or the individual packs listed below.
While the modding community for Assetto Corsa on PC is massive (hundreds of thousands of cars and tracks), official Kunos content holds a specific advantage: Official packs feature consistent physics, proper audio sampling, and optimized 3D models. Furthermore, many online multiplayer servers—especially those running "Track Day" or "Competizione" formats—require specific DLC. If you join a server running the Porsche Pack III cars without owning it, you are kicked. assetto corsa all packs