If you're going to use .45 "Long" Colt, why'd you buy a Judge? Why didn't you just start out with a revolver meant for .45 "Long" Colt?
The Judge's cylinder is so long that the .45 LC bullet is going to be travelling for miles before it finally reaches the barrel's rifling. That's not gonna be good for either accuracy or velocity.
Further, that long, long cylinder complicates concealing and carrying the gun, and limits your choice of holster.
Anyway, the .45 LC is quite adequate—maybe even "more than adequate"—for self-defense.
You may have trouble finding it for sale, though, since its used most often in cowboy-style shooting matches, not defensive carry.