Yamaha makes a 19' and a 21'. I've never owned or driven one, so I cannot comment with personal knowledge on their maneuverability, fuel efficiency, etc, but they sure look nice. And as Billy Crystal's, "Fernando", used to say in those old SNL sketches, "it's not how you feel darling, it's how you look!"
I've heard 2nd/3rd hand that they tend to be less expensive to buy than a comparable I/O boat and with no outdrive hanging down, can go in shallower water. I have also heard that the jet is not as precise as an outboard or I/O in tight docking situations.
Think, being the researcher that you are, I'm sure you will carry out the utmost due diligence on this!