About 3 1/2 of an 8 hr CE class I attended this spring, was dedicated to fiber cement siding products. We heard everything negative about them, but that. It seemed more like a warning class than anything. I've got to believe, if the instructor was armed with that information, he would have passed it on. I also saw and had in my hand, a piece that delaminated like layers of shale after sitting in a cup of water for a little less than five hrs. This was not done by the instructor. Another inspector did it out of curiosity. About sixty others including another who frequents this forum, saw it. I'd rather not say here, who's product it was.