Is a 2-piece or 3-piece luggage set better value?

For most travelers, a 2-piece (carry-on + large checked) covers the common use cases of weekend trips and one- to two-week vacations. A 3-piece set adds a medium checked bag that's useful for families or couples splitting items between bags, and per-piece cost is usually lower. Reviewers consistently note that the medium 24-inch piece is the one most people underuse, so if you rarely travel as a pair, the 2-piece is the more honest buy.