The no-hub also won't carry the weight that hub and spigot cast iron will. I've seen a few roof drains come apart in business ceilings because the old cast iron

The no-hub also won't carry the weight that hub and spigot cast iron will. I've seen a few roof drains come apart in business ceilings because the old cast iron was replaced with hub and spigot, and no one adjusted the spacing on the clevis hangers. First major rain, and there's too much weight for the no-hub couplings! You can of course run extra heavy no-hub couplers (four or more worm clamps per joint).