I'm glad someone asked this question actually, Looking at it and even picking it up it looks and feels like its a solid material as if it was some kind of metal, but purely by the weight you know its not. But with out a lot of reinforcing it is pretty rigid, just with that perfect amount of give, so when putting it on and off its a little easier. The glue wash process I use helps with the rigidity as well as the flexibility without damaging any of your hard work. I used to be a Pepakura and Fiberglass advocate, but since moving to foam, I would never turn back. I believe whole heatedly in using foam as a base and for most details but if you wanted to add 3D printed parts (if I had a 3d printer I would) or smaller fiberglass details, it would all mesh really well. Some of my smaller details are rigid items like nuts and bolts, plastics and other things like that. The thing I find a lot of people don't remember is that just because your using foam, the entire project doesn't need to consist of it. Some people would disagree but with a little pre planning and thought, you can achieve twice the detail in half the time and if you make a mistake, its as simple as cutting another bit of foam out and doing that one piece again, with pep and resins you would have to figure out a way to cover a hole or damage depending on how big the mistake was and what it was that went wrong, then if more resin was required you would have to mix it, apply it wait for it to dry or stop being tacky, fill, sand it and so on. I find with foam that less movement is restricted when your wearing it too. But having said all this, its each to there own, both methods have there pros and cons ( I just think foam has less cons haha ) and what ever you decide to use I'm sure it will turn out awesome !!. I'm glad to hear that my project is inspiring others and that my posts are helpful, more then anyone could want. I don't mind answering specifics ether so don't hesitate to ask any questions, I may not be able to answer them straight away due to my work scheduled, but I will answer them.