I'm going to weigh in on the side of "one never knows." The AR/AK platforms are perfectly viable self-defense weapons (with the caveat of something like the non-penetrating TAPS)...I usually have an AR around loaded with the TAPS.
But when I look at home defense in terms of pure risk assessment, I am looking at 1-3 armed potentials, not a determined squad loaded with battle hardware. I would probably be facing handguns at the worse. My handgun is the immediate response weapon of choice — it's always at arms' length...if I am fighting defensively at bedroom distances, I transition from handgun to 870 Vang Comp loaded with tactical buckshot, with my Sweetie backing me up with a 12 gauge double...I'm pretty sure I can hold the bedroom until the cavalry arrives.
If, however, there appear to be threats scattered about...maybe outside shooting in...I want a rifle. The advantage of a lever gun is that my .44 Trapper delivers a 250-grain Winchester bullet specifically designed for massive expansion in thin-skinned game — that would be us — at about 1500 fps, and it can be delivered with extreme precision, rapid follow-up shots and topped off virtually forever (and I keep a 50-round box of 240-gr JHP Black Hills around for just that purpose). My goal is to guarantee that anyone I shoot stops...right friggin' then! If I have the lever gun, and my Sweetie has the AR, once again I'm pretty sure we can make it through the night. And we've still got the handguns in reserve!
I'm working with Chiappa on the breakdown '92 .44 Magnum because I feel a lot more comfortable when I travel with guns. A lever gun is acceptable virtually everywhere...even places where an AR will, sadly, get me thrown in the slam. If I can get the gun I want, it'll pack as easily as a handgun. If I carry my 3-inch 629 or that 4-inch ultralight 329, I've got a handgun/rifle combo in the same very powerful caliber...as handy as it was in the Old West.
Why might I want to carry a rifle on the road? Because I might need it. I was moved by a friend's story on 9/11...when the flights were grounded, he had to drive across the country to get home to his family...he was armed with a J-frame and 5 rounds of .38+P ammo. "It's a drive," he told me later, "that I'll never make again...sure nothing happened, but that doesn't mean nothing will happen the next time..." I travel a lot, often to the People's Republic of California. A rifle would be...a comfort. Heck, In Kali an RPG would be a comfort! I can conceive of a situation where I might have to make a long drive home through a troubled landscape, and I'd like the firepower.
Also, you can't argue with the legal ramifications of using an "assault weapon" to defend yourself. Brother Ayoob has been very clear that in a shooting situation, you will have to defend your life not once, but twice — the second time in court. I would much rather my attorney hold up "John Wayne's gun" to the jury than "Rambo's gun."
Will I give up my ARs for lever guns? NAAAAAAWWWWWWW! Do I feel comfortable with lever guns for defensive weapons? You betcha!
Michael B