Yep, even my good glass pants from FGS will crack and they are a lot thicker then the ARF pants. I have sanded off the paint a time or two and discovered the glass was fine but the paint itself was cracking from the vibration and flex. I haven't tried it yet but I was thinking of giving that motor cycle paint that bends and flexes a try sometime. So far it's still just a thought. Like Jay mentioned, I leave the pants off most the time unless the plane is going to be shown for some reason.