Given the weight of a heavy duty frame and the heavy duty roof, is there any point in having them on the inner tiles of a vehicle? and since roof tiles don’t need to be placed on the same tile of a board or quarterpanel, why bother with heavy rioofs at all?
If I’m not mistaken impacts will propagate through your vehicle a bit. Which means if you hit something hard, your exterior heavy duty frames will bounce off, then your internal light frames will shatter. Not sure how that applies to roofing though.