While I dislike the looks of both, I think you would be better off with the S&W than the Taurus.
I've had a .45 Colt/.410 Contender for years, and have played around a bit with it, although not with the new crop of "defensive" .410 buckshot loads.
Personally, if I were going to use a Governor (or anything like it) for defense, and were NOT going to use .45 Colt ammo, I would pick .410 slugs.
The advantage to buckshot is you get a pattern, but at home defense distances, and with the small number of shot in a .410, this is a very small gain, and weighted against the smaller mass of each shot (round ball) I don't see any advantage for personal defense over a solid slug.
And .410 slugs are not exactly wimp loads compared to many common defense cartridges. Winchester says their 3 inch slug is 1/4oz (call it 110gr) at 1800fps. Now that would be out of a 18" or longer shotgun tube, so, out of a 3 inch handgun, what is expected? 1200fps? More? Anyone chronographed .410 slugs from one of the Governors?
I would think, even at 1000fps, the .410 slug would be reasonably bad medicine, and I think it likely you would get a bit more than that in velocity. That's at least a match for a 9mm.
Perhaps some testing is in order...
There is one good thing to the whole Judge/Governor type, and that is many people are buying them, even if they are mistaken about how good they are for defense, at least they have a gun.