Honestly, I don't have a gun, been to the range several times though.
Here's my advice - any gun is sufficient for home defense if your accurate enough with it - even a .22 will kill if you're really accurate. Go with what you can hit your target with from a reasonable distance away (within the home scenario). No point getting a bigger gun if you're just shooting space around the target.
I'm pretty good with a 9mm, ok with a .45 or a 10mm and I'm all over the place with a .50cal (though I felt moderatly good that at least I hit the general vicinity of what I was shooting for on the target, but there wasn't much in terms of grouping!