We must’ve been fortunate with our wooden door because sanded down to bare wood and 2 coats of Sikkens and it looked identical 7 years later. It may not have sealed amazingly but certainly wasn’t high maintenance or warped or fouling. Anyhow post-extension building we went Endurance composite but amazed at the effectiveness of Sikkens. We used the very watery but amazingly durable couple of coats of Rubbol Satura on an adjacent door to the garage and similarly it was unfazed after 7 yrs south east facing. So yep composite the way to go but Sikkens applied as per their guidance can be depended upon.