Cost-effective; extremely strong when bonded correctly. Cons: Can rot again if water penetrates the seal.
Tilt your outboard up and apply downward pressure to the lower unit. Any visible movement or "smiling" (the gap opening between the motor and the transom) is a red flag.
Coosa Bluewater is a fiberglass-reinforced foam that is 100% rot-proof. Cons: Significantly more expensive than wood.
Grind the inner skin down to fresh fiberglass to ensure a mechanical bond.