The boat we had intended to buy was the Ultimate 14.5. But when a clean used Ultimate 16 came on the local market, with paddles, for less than the discount price on the 14.5, we jumped on it.
Our dilemma of how to cartop the boat on our (tall) Honda Element was solved. We eliminated the Yakima Hull Raisers ("J" saddles) and added pads to the crossbars. Now, using the extendable Boat Loader bar to get one end of the boat up high, Carol and I are easily able to put the inverted boat on the car and take it off again.
Compared to the 14.5, the 16 doesn't turn quite as easily, but seems to be about the same in all other aspects. The extra room between the paddling positions makes paddle clashes all but non-existent. We carry our dolly in the rearmost space, a large cooler aft of the front position (between my feet), and the little doggie goes wherever he likes!
We've done up to 4 hours at a time in the boat, and I come away with NO back issues at all. That's a relief, since my attempts at getting friendly with sea kayak seating just about had me giving up on paddling. The boat is so stable that I can pull alongside a dock, Carol can stand up and take the dog ashore to do what he needs, and re-board with no fear of capsizing.
For those looking for stability, comfort, and ease of transport, look no further.