If you want diagonal cutters, the 3 best choices out there will be Knipex, NWS, and probably the Klein 2000 series. I only say probably, because those are the only models i dont personally own - that said, the standard Kleins are still pretty robust, so if the 2000’s are improved i have no doubt they will hold up just fine. Channellocks just wont withstand the cutting of hard materials, and it wont matter which model you buy - they all use the same metal. 338’s (if I remember correctly) are retired now, so you’d have to either find an old set online somewhere, or buy the newer E338.
I can tell you this much - the Knipex are pretty much bomb proof, and the NWS which i just recently bought (standard style, already had the fantastico - those really aren’t worth it IMO) seem just as good with the jaws having a slightly nicer tip on them - but its not like ive used them for a year to really abuse them yet.
The knipex mini bolt cutters will amaze you with what they can cut. Realize there are several different models, and some have a notch in the back of the jaw or “throat” (for lack of a better term) for really hard material.
Klein also makes these monster diagonals now. J2000, so they are the heavy duty series also. I dont have them yet, but they are basically lineman pliers made into a diagonal cutter. While that doesnt mean the jaws wont get damaged on something you shouldn’t use them on, the sheer size of them is impressive. I’m not suggesting these are the best choice, but the fact they are made just makes me want them.. lol. If you zoom in on the pic, you’ll notice the cutting edge is slightly recessed from the end of the jaw, so not the best choice if you need the very tip of the tool. For cutting things like tie wraps that are already pulled tight around something, this could be very annoying.
For what its worth - Channellock also uses a different style of cutter design. Instead of 2 sharp edges, they use a cutter anvil combo - so one edge is duller than the other. This is meant to help the cutter edges from skipping over each other when pressure is applied, which do happen on the standard Klein cutters i have.