Anodising type 2 does come off easily, with my HA (type 3) lasting longer, but I find it chips more easily rather than wear. Yours however looks pretty worn. I never carry torches with keys though, Always has a pocket for its own.
My HA is nitecore, and sunwayman. Nitecore is a good balance between hardness and wear, while the sunwayman is harder and thicker so as a result its more scratch proof, but more prone to chipping.
HA3 chips pretty easily. Sunwayman HA is some of the best I've seen. The problem with HA is that the underlying aluminum is very soft, and once the support is gone, the ano just flakes off.
Good thing we aren't out to impress people with our keychain lights or think about ever reselling an edc ..I like a light with very even wear ..Chips might bug me a little ..probably just makes it brighter .;)
I bought my ITP to carry on my keys but cant bring myself to do it. I use the clip. Guess ill just have to buy another light for my key ring. A stainless one.