Folders with a thin Carbon blade (probably the best for most jobs, IMO) are hard to find, giving Opinel a few points by default.
Overall Opinel makes a very usable knife for the price. They are good for cutting, easy to sharpen, don't weigh much at all, and can be replaced cheaply.
As Mycroftt said, it's like a folding version of a good old standard Carbon steel kitchen knife. Great for cutting food. Another common vein among knife collectors is often cooking. We have had many food prep discussions on usenet.
I, and I imagine other knife people, like them as an example of how a sensible blade shape and simple, decent carbon steel can make a useful knife for not much money. The blade is not very hard, but the steel and shape make it cut like crazy anyway.
Even those of us with very expensive knives are very amused by cheap knives that offer good value. It's nice to have a cheap knife that doesn't make you worry about ruining a good $100 blade, and Opinel is one of the few offering such a cheap knife that is usable and doesn't look like a modern cheap POS from Pakistan or China. It IS cheaply made, but it still works good enough and looks nice.
It's nowhere near the "best" knife I have, but it's probably in the top 10% for most appreciated.
