Dingo:

Initially the strength comparison is a wash. But unless the beams are carefully fitted into the formers they will shake, and cause the glue joints to fail. But if you put ply gussets between the beams and the back of the firewall, the composite mount wins.

Age? My oldest flyable airplane was built in 1960, oldest r/c plane is more than 20 years old, my oldest (and first) r/c twin is about ten years old. It's in my avatar. And none of these planes have the engines on wooden beam mounts.

Bill.