For hot-weather travel, both fits work, but it depends on your priorities. Oversized tees offer more airflow and a relaxed, street-style vibe, but they can feel heavy when wet. Regular fit is more versatile, packs tighter, and tends to look neater in photos. If you're moving around a lot and want breathability, go oversized; if you want a clean, all-day look that's easy to pack, stick with regular.