Let me preface my remarks by noting that I do not have one, so my opinion is unencumbered by relevant experience. You may wish to value accordingly.
Here are the issues in my opinion (again, for what it's worth). 1) Freebore. That's a fairly big jump for a 45 cal bullet, so I would imagine it may be hard to stabilize bullets, with cast bullets it may cause distortion and further aggravate accuracy, and I would think it could lead to more rapid throat degradation. 2) 410 patterns are tricky enough from a smoothbore, now you've got shot spinning down the barrel in the shotcup (that's smaller in relative diameter than it would be in most smoothbore barrels) and then hitting a short internal/flush choke before exiting. I can't imagine what kind of patterns it will give you beyond 10 yards.
I imagine it would be only slightly more useful than a Taurus Judge, in as much as it has some heft and could be effectively used as a club.