Although I don't have a sickle or gremlin to post, since I haven't built one YET!. I have built a Coro Stang, (2 in fact) a Mig7, a FNS and a couple other non-mentionables. Do they fly as good as "foam" you bet! Does the heat in Hawaii effect them? Heck ask the combat guys here who flys them and wins! So is foam better? I think it's all in the pilots perspective if you ask me! BTW, the sharp leading edges? Where have you been? Stop by, read some posts! You can make a round leading edge no problem you can use foam for ribs if you want to keep a "shape". Does BLACK get hotter than WHITE? yep!

I am curious why you think the airfoil shape will change at higher speeds, there is a SPAR IN THERE ya know!