Stainless Public Defender owner here, IMO the little extra to pay for a steel frame model is worth it. The extra weight helps keep recoil manageable with certain .410 loads.
Haven't tried shooting .45 Colt or Schofield yet, but intend to by the end of Summer. .410 is a tale of two ammos, Federal 4 pellet 000 Buck and any other 3 pellet 000 Buck. 3 pellet has very little recoil in my PD and it's downright pleasant to shoot, but the issue is accuracy. From the two times I've shot steel, I get more hits with the Federal 4 pellet load than I do the 3 pellet loads from other manufacturers. The only downside to the 4 pellet Federal ammo is the recoil goes up to just below the pain threshold. Two shots with the Federal and you're feeling it, whereas a 25 rd box of the 3 pellet stuff you feel nothing because it's so light in recoil.
I'd have to shoot more of the Federal, but given the recoil and distances that these Judge revolvers would be shot for home defense situations, I have no doubt the 3 pellet stuff will work fine. Inside the home is a defense situation where you don't want super deep penetration. The 8 to 12 inches of penetration that the 000 Buck will give you is fine considering you're getting 3, 4, maybe even 5 pellets per shot and multiple wound channels.
Remember, killing is irrelevant in a defense situation, it's stopping. If that stopping is done by killing or making someone turn tail and run with several slugs of lead in his lungs or intestines, then the threat is stopped. You don't need an exit wound to achieve that.
As for .45, will it be as accurate as a standard revovler? No, but the accuracy with the .45 will be good enough for typical defense distances. The only issue I have shooting .45 in the Judges is the cylinder throats are huge, like sized for .45-70 bullets huge. Using standard lead bullets means the bore is going to lead like crazy. I'm looking at solutions for this, one of which is a hollow base wadcutter bullet. Given the long chamber, that distance should give the hollow base enough time to expand to seal the gases at the throat and the long bearing surface in addition to the hollow base should grip the rifling better and improve accuracy. Time will tell, I have to test this theory.
I do like wadcutters for .45, good bullet that doesn't rely on bullet expansion to work when it hits the target and even at low speeds the big bore revolver calibers like .44 Spl and .45 Colt sill hit plenty hard and penetrate well for the situations where penetration is needed.