definitely watch the weight. I had this plane on a Saito 180 and it was very gentle, landed at a crawl, wonderful airplane. Still kick myself for ever selling it. A fellow club member had one with a Brison 2.4 as you've mentioned, and his report to me was that it was very apt to tip stall. I'd say do the best you can to watch the weight and see how it goes. I wouldn't worry about the foam in the turtledeck, could you imagine how much foam you'd have to remove just to save one ounce? Not much of anything to be saved there. I do remember the gear being kinda heavy on this one, so you'd do well with carbon there, plus with the gas motor, you'd be saving weight in the right place there.