Looks like it didn't get anywhere.

http://www.questarmarine.com/tech.htm

Maybe construction costs, or maybe it wasn't all it was touted to be.
Getting fuel efficiency from land vehicles involves engine efficiency,
weight, aeordynamics, and rolling resistance friction.
Those are the basics, and the rolling resistance is basically the
least of the problem, being handled by bearing and tire design.
With a boat you've got all that except the "rolling resistance" is
replaced by water friction and water displacement at speed.
This hull tries to address that.
I'm far from an engineer but its seems to me that boat designers
should be able to get closer to auto efficiency than they have.
But maybe not.
When you look at a planing boat you see there's a small pad of the
bottom that's actually in contact with the water. Might make you
think that it shouldn't take much power to move the boat on that
pad. Took some power to get it up on plane, but then less to keep it
there.
Must be the energy losses in the prop moving water. Just not as
efficient as rubber on the road. Water slip.
That's where Froggy should look for a breakthrough.
The tunnel hull seems to offer some promise. Pressurize the water
feeding the prop using a tunnel design. Or maybe reduce the pressure
and increase the velocity with the tunnel design.
Like I said, I ain't an engineer.
Maybe use some of that hi-tech coating material on it too.
Should be able to come up with one that repels water.
Antiwaterium?
How bout it, Froggy?

--Vic