Does an 80ft power catamaran have more space than an 80ft motor yacht?

Yes, significantly. An 80ft power catamaran often feels closer to a 100–120ft motor yacht in usable space. Because it has two hulls, the added beam creates much larger saloons, wider aft decks and bigger outdoor entertaining areas. On a motor yacht eight guests are spread vertically across decks; on a power catamaran they spread horizontally across a platform nearly twice as wide.