What do you know about the "Azdel Composet Sidewalls"?

Well, only time will tell. The thermoplastic is being used for fencing, hand rails, decking and other construction/structural purposes. It does not age well, but it is exposed to weather 24/7, so its not a fair comparison. Luan plywood is at least 3 cross plies thick and glued. This is why plywood is strong for its thickness, but it will degrade when exposed to water. Gluing the Azdel into the sidewalls, or roof does add a large amount of strength. Lake everything new, it will take time to really tell the tail.