I am an occasional user: on-site maintenance work mainly. I've used a pair of crimping pliers for years with different slots for each size. With the onset of codgerhood, it's getting harder to see the slots and pick the correct one. I was putting together a couple of VFD panels and control stations at home and needed some ferrules. It was as cheap to order a Preciva tool with an assortment of ferrules from Amazon with prime delivery as it was to go out and buy the 3 sizes of ferrule I needed locally. I was seriously impressed with the tool. It is a 6-sided one and saved so much frustration that it went straight into my site kit once I'd done. The 6-sided crimps are great for a lot of terminals, but I felt the square ones would be better with the cage-clamp terminals on circuit breakers, etc , particularly in the bigger sizes. I ordered a set of them as well. There were no 4-jaw Preciva listed on Amazon prime at the time, so I bought a tool only (no ferrules or case).
It seems just as good as the Preciva one. I'd be prepared to bet they all come off the same production line and, to be honest, the only reason I recognize the Preciva name is that it's on the case and I see it every time I use the ferrules, whether I use the 6-jaw tool from the case or the 4-jaw from my toolbag.
I do mainly mechanical stuff out on sites with a bit of instrumentation electrics, faultfinding, etc, at work, but we had an installation job the next week. I lent the crimpers to my colleague, an electrician. He tends to moan, continuously, about pretty much everything. Remarkably, he didn't moan about the crimpers at all. After the job was finished, he ordered a set of the Precivas, together with the 4-sided crimper on its own.
We are both agreed that a panel builder using them for production work, day-in, day-out, in a clean environment would probably benefit from Knipex or similar high-end tools. However, for occasional users on jobsites, where they are likely to get wet, dropped from a height or lost, long before a set of the "better" ones would wear out, the cheap ones are plenty good enough.