I have a Stoeger double bbl coach gun in 20 ga.
It's a lightweight classic that's short enough and handy to use for home defense. While I'm not a cowboy match shooter, I've seen some amazing performances from cowboy match shooters using shotguns just like mine.
I can't recall reading about a shootout inside a home in our town in the last 20 years, or a home defense scenario anywhere, really, that went further than 4 rounds of 00 Buck. But if that should occur, there are several handguns nearby that would offer additional options.
I think a coach gun would work fine in a home defense or truck gun role. The idea is that you're not going to war or taking on the Crips, but you're facing one or two assailants who aren't going to be happy looking down the barrels of a coach gun. It's as likely as any other shotgun to remind them of urgent business they suddenly remembered they have elsewhere...
Treat everyone you meet with dignity and respect....but have a plan to kill them just in case.