I've been building with foam for a couple of years now. Not park flyers either, we're talking Combat!

And yes, I find working with foam fast and easy. And yes, I've done a few of my own designs including one I've kitted for a few guys who have wanted one. (note, I'm not in the kitting buisness, some guys asked if they could get one, so I made a few extra and sold them at cost). I have the building instuctions for my Rapier design posted on www.MidAtlanticCombat.com if you're curious.