Buyers should prioritize Aluminum (3003 or 5005 series) for its lightweight and rust-resistant properties, or Stainless Steel (304 or 316 grade) for high-end architectural finishes and corrosive environments. For industrial use, Galvanized Steel offers high strength. Ensure the thickness (typically 0.5mm to 3.0mm) aligns with structural requirements, and verify the coating type, such as PVDF (Polyvinylidene Fluoride) for 20+ years of exterior weather resistance or PE (Polyester) for cost-effective interior applications.