It would mean buying a thrid type of pistol ammunition, though I'm getting over my desire to have many guns in few cartridges (not as much fun, you know).
As I said, I also like big bores, though bore diameter matters less than mass/velocity, and I think 158grns @ 1300+ FPS will do quite nicely. I'll pass on the 125 grain stuff, I think, I like heavier bullets.
Probably use .38 +P for home defense...my house has thin walls.
That said, though I really like the .45 Colt round, the .357 would allow me to practice with my revovlers more, as frankly, .45 Colt is EXPENSIVE to shoot, and most of the cheap stuff you can get is really anemic, which doesn't prepare you for shooting with the more powerful self-defense stuff.
Durn it. You're all going to make me end up getting TWO Vaqueros, you know. I already want one in .45 Colt. Watch me go and get one in .357, too.
Geez. This is an expensive hobby.