Ref the C17 ...The only problems I've noticed with xp 11.55 is the main gear trucks don't sit flat on the ground, and in experimental flight mode it seems to need a lot of up elevator to keep from diving into the ground, but it eventually settles down as speed builds. There could of course be other problems I haven't noticed and it is officially an xp10 model so your on your own if you choose to use it in xp11
Matt