No...foam core construction will not be just as strong. To clarify I will say that you could make a foam core boat as strong as a wood core boat...but you will really end up having a fiberglass boat filled with foam...albeit foam sheets, or strips. For your foam core boat to equal the strength of the wood core boat you will have to add more fiberglass, and cute little stiffener struts, fillets, etc. The boat will be as heavy...probably much heavier. If you're looking for quick, cheap, and easy go with S&G. Always keep in mind that S&G is not inferior to strip built...just another method of building a quality boat.