Between the two, Channellock cutters are not the same quality as kliens. Also, Klein now has their heavy duty cutters to pick from also. The jaws on channellock will not withstand cutting hard material and surviving. The problem with channellock is they use the same metal for everything they make. There is no difference in hardness of jaws between any model. That's fine if you're cutting copper wire, and general things - but one hard item will ruin the cutters.
Just to note, the heavy duty Kleins are not in that line up. The Fantastico (NWS/Irwin) cutters are very high quality, but they are really only good if you have a very specific need to cut something that's very hard and very thin. The increased leverage comes at the cost of jaw opening, and the bottom throats of the jaws are very small. Not being able to fit what you're cutting all the way down to the throat sacrifices leverage, thereby defeating the purpose of those specific pliers. Also, yours hands need to do a lot more work with them since the handles need to be opened almost twice as wide to get the same jaw opening as standard high leverage cutters.
A common issue with Kleins pliers are their needing a lot of time for the joint to be broken in, and while smoother when new, the cutters sometimes will have an issue with the jaws skipping over each other when a lot of pressure is applied. This is why channellock uses a cutter and anvil design on diagonals. One cutter tip is wider and flatter than the other, so the jaws cannot skip over each other..
The best all purpose cutters, the "gold standard" if you will, are the Knipex. There is no slop in the joint, the joint is still butter smooth when new, the jaws don't skip, and they are some of the hardest rated cutters that will actually deliver what they promise. Also, they are a straight head design, unlike the heavy duty Kleins that are slightly angled. Another difference are jaw shapes. The Klein are a little less wide, and come down more to a point. The Knipex jaws are also a bit longer than the Klein, so it will cut wider material with a single cut. While both points are not a big advantage for most people, they are worth noting. I've never NOT been able to cut something with my Knipex against a flush surface. The Knipex I use are the 8" models. They get used and abused at work and the cutters still look new and are still very sharp. I own and have tried most brands people would consider buying, and they are my favorite by far.
I know it's a preference thing, but I really don't like the wide grips on the Irwin. Especially work with gloves on. They don't fit into small pouches either due to the grips.
Anyway, for cutting thin stainless straps, I've always found tin snips to be the best. I use my Knipex diagonals all the time though, and just grabbing a two or three layered stainless strap, they will start the cut and I'll just use the jaws to rip them open the rest of the way. The cutters sustain no damage, and it's the stainless straps that will usually destroy inferior cutters. I ruined a brand new pair of channellock diagonals within 2 hours of using them the first time with those.
Also worth noting for the OP, many of the cutters in that lineup are for electronics, not really what I think most people are looking for. Some others are end nippers, not really something that will replace diagonals either.. one is a terminal crimper, another are ring nose pliers, another are bolt cutters, and one is either a cable or coax cutter. While it's a nice picture, there are only 3 "general sized" diagonals most people would consider buying as a dedicated diagonal cutter. Of those, one is the NWS/Irwin which I already mentioned, another is a 6" (I think) Knipex twin force I believe they are called, which will exhibit similar restrictions as the Irwins, and the last looks to be a well used pair of standard Kleins.
For home and general use, channellock will be fine, and they are more budget friendly too. For professional electrical use, Klein and Knipex will be better choices across the board.. when it comes to pump pliers and diagonal cutters especially, the Knipex alligators / cobras and diagonals offer some real advantages.. for automotive stuff I think the channellock pliers are fine too. I have channellock at home, and Knipex for work.. those are the choices I made based on my experiences using the tools. I don't own the Knipex needle nose pliers, but I believe they are designed to let the jaws flex opposed to Klein or channellock that use rigid jaws for those.
