It really sounds like there are just a lot of valid arguments for all types of construction. They all have their strengths and weaknesses. I have been reading extensively on the net about types of foam PVC, polyurethane, polystyrene, and different glasses and epoxies. I'm fairly decided that I want to try my hand at a composite plane. In honesty, I really hate aluminum construction. I've been helping on a friends Sonex. It's just not me. Too confined. Too rigid. Glass is more "open" or "free".
Now on to deciding what airplane to build.
Thanks everyone for your input. You have been very helpful.
John