Be aware that fiberglass is a material that is created in the shop, so quality control and conditions of the working premises have a major effect on the physical and structural properties of the final product. Metals are created in large foundries under strict quality control and shop welded on the edges only, while fiberglass is created almost entirely on site during construction. No one material is stronger than the other per say, they are only stronger per pound. How the material is used has a large effect on the strength properties. In fact they have included a technical discussion on how their wood method is stronger and lighter than aluminium.
Weight is a big factor in choosing which material and method for construction.
Boats essentially cost by the pound so the heavier a boat is the more it will cost. If the vessel is light and the materials are not high-tech then the overall cost of the finished vessel will be less. Weight in a small boat will give it the feel of a large boat but a lighter larger boat would cost the same. The impulse to add weight for the sake of weight is a strong one that needs to be controlled. Strength is required but added unnecessary weight puts a burden on the structure which may over stress it.