MonkeyBoy54321The best carbon steel knives will take a sharper edge, are easier to hone, and will be both tougher and harder than the best stainless ones. Literally the only disadvantage is you have to be diligent keeping them clean.
herringonryeI don't think the 'tougher and harder' are true. There are plenty of stainless knives heat treated to a higher Rockwell rating than than most carbon knives.
KazInVanAre you talking about ZDP-189? That's the only stainless I know of that any knifemaker will harden above the 63-65 common for good Japanese carbon steel knives. Supposedly it beats any carbon steel in edge retention, but it's not very common, isn't truly stainless, and usually twice as expensive as an equivalent knife made with Aogami or Shiogami. If I was going to spend that much I would go with a non-stainless powdered tool steel like HAP-40, which isn't as reactive as carbon steel, even harder than ZDP-189 with the same or better toughness. (It's a little crazy all of the steels I just mentioned are made by Hitachi, but I can't think of any better ones made by other companies.)
I have a cheap Chinese cleaver made of mystery carbon steel that compared to either of my VG-10 knives, takes a finer and tougher edge that lasts longer and is easier to sharpen. Though it will rust instantly if you leave it wet and don't oil it, and will turn onions black if left in contact with the blade.
MonkeyBoy54321As mentioned below, a keener edge, but also some people want a blade with a patina and not these shiny chrome blades. Think of it as jeans enthusiasts that want personal "sick fades" on their jeans.