Regarding Opinel's Inox... I have a #10 Inox that I've treated quite roughly. The steel, as most folks know, is Sandvik 12C27 hardened to around 58Rc. In contrast, the Carbone is close to 1086 hardened to around 56Rc.
Both take similarly fine edge. On the stone and cutting wood, the edge of the Inox lasts longer and feels more like Schrade USAs old 1095 (which was hardened to around 58Rc too). 12C27 is a fine grained stainless and both it and the Carbone will dent if treated roughly (like cutting cardboard with metal staples, battoning through junk wood, cutting things off of metal pipes). Being harder, the dents in the Inox are deeper and more profound and don't come out with a simple run on a stick. But, I've not gotten it to chip either.
I've used the following stainless steels: Buck's old 440C, Buck's 425Mod, Buck's 420HC, Schrades 440A, Case's 420HC, Victorinox Inox. Opinel's 12C27 feels the most like Buck's old 425Mod. It takes a very, very keen edge. Much easier to sharpen than Bucks 440C. I like it better than Buck's 420HC, and like that steel quite a bit. I wouldn't hesitate to use the Inox for everyday use and would only demand the Carbone for a beat on it knife, but then, I would pick the Carbone above all of the others I've mentioned just because it handles abuse so well.
Regarding one hand open/close, here's how I do it.
1) Unlock the collar.
2) Flip the knife so the collar is facing down.
3) Pinch the spine of the blade with thumb and first finger. This is easier with a N9 or N10. On 8s and smaller, sanding out a bit of an easy-open dent sort of helps. A picture of an e/o N10 is below. It is also easier if you do this while pressing the knife against your thigh. Lastly, you can always resort to the " coup du savoyard" by tapping the heel of the handle hard on a firm surface (like your hip bone, ladder, whatever) to pop the tip up a bit.
4) Press the handle down and away with your second and third finger. At this point, the knife will be about 1/4 of the way open.
5) Holding the spine firmly, hook the butt end of the handle on your thigh and lever the knife to the fully opened position. At this point, you will be holding the blade in a "choked up" position.
6) Place the butt of the handle against your thigh (or whatever) to stabilize the knife and slide your grip down to the handle.
7) Lock the collar.
For closing:
1) Unlock the collar.
2) Close the blade by pressing the spine against your thigh (or whatever)
3) Lock the collar.
This process is
slow compared to modern flippers and, unlike modern flippers, it
requires practice. It is also
safesince there is no spring involved. This particularly true when closing it, but it is also true when opening compared to one hand opening lockbacks using the same technique.
Buck 110 and Opinel #10 by
Pinnah, on Flickr