Merino excels at odor control and comfortable warmth across varying conditions, making it ideal for repeat wears between laundry cycles. Technical synthetics shine in quick-dry performance, shape retention, and affordability. Blend strategies: merino tees for odor management, synthetic mid-layers for durability, and hybrid socks that cushion without overheating. Test pieces at home, noting drying time after sink washing, so onboard routines feel smooth, predictable, and pleasantly low effort.
Down offers unparalleled warmth-to-weight and compressibility but falters when wet unless treated. Synthetic insulation performs better in damp climates and dries faster, though slightly bulkier. For shoulder season sea days, a thin synthetic jacket or vest often wins, layered beneath a shell. If choosing down, protect it with a reliable waterproof, and store compressed only briefly. Prioritize responsibly sourced fills and baffling that prevents cold spots during gusty moments.