Not a new concept. Savage M24 series. I thought those were cool when I was a kid, but really, what can it do that a 20 gauge double with appropriate loads in each barrel cannot/ I mean, I can go slug in one barrel, 6 shot in the other, can take hogs and deer to 50 yards or squirrel or rabbit with the shot load. I think just a standard double, SxS or O/U, is a more versatile gun.
But, JMHO. If you got the hots for it, GET it. Someone here might be able to shed light on whether it's well built or what.