Idk, I've never really seen anyone get killed with unarmed (unless it's after a series of bashing), but I have seen plenty killed with a blaster. Armor and hard boiled (mush skill) makes unarmed combat much more useless too. If your target is a mush that anticipated unarmed combat, it's not going to be very useful at all. One of my fights had about 16 total punches on me, as mush with armor and hard boiled, and I lost only 3 HP.
Blaster do have 3 charges and only one of those will hit. But it still seems like a better use of AP than 3 punches. And sometimes you injure yourself too but if you're in a situation where you have to fight, injuring yourself is not the worst outcome. Unless it's a surprise backstab on someone who may be a mush but isn't actually a mush. Those are times where you don't want to accidentally cut off your tongue or break a leg.
Shooters get free shots and headshots though. I know headshots can bring someone down from 16 health to 0. Ian's weakness is a guy with Shooter skill and a blaster
I'm actually be more inclined to knife, even with Solid. I got about 3 critical kills out of 9 with the knife, and roughly 0 out of 3 kills unarmed, so I'd say criticals matter a lot too. I've never self injured once with the knife despite what the forums and wiki says. And most importantly, once you're holding the knife, people can't use it against you.