Yup, and all that space on both sides of the engine.
Yeah, all that space is just wasted. Unless you want to service the engine. Again, I understand some owners consider that "optional".
Oh, and then there's the ability to add sound insulation when the engine sits lower - and there's only one of them. But hey, if you're really proud of how your engines sound and want to share that with your passengers, then that wouldn't be a feature you'd want.
And doubling the number of hull penetrations - everyone knows that you increase seaworthiness by punching additional holes in your boat. That's just common sense, right?
Keith