What do I expect from a knife... That's an interesting question.

I have basically 3 "classes" of cutting tools.

1 - Chopper.
That one gets the ugly job done. Chopping down trees for fire, shelter, digging, prying a little (yes... I know). This one is not always carried as survival gear, but depending on the situation, it does. For that kind of use, I want a tough knife... Edge retention is useful, but toughness is the most important, so I stick either to soft carbon steels (Tramontina machete), or tough blade geometries (tomahawk, hatchet...). I also use a Becker Brute (BK1) with modified geometry (ground to a pretty wide scandi edge) regularly.

2 - General purpose knife.
That's always a fixed blade. It's not meant for chopping or prying, so toughness is not a real issue, and 4 inches of blade or so is more than enough. I like them tough, but the primary thing is sharpness and edge retention. I want them to be good cutters, and I want them to keep an edge. The best I've had so far are Scandinavian grinds. They really are worth a try. I use a Mora #1 (I prefer KJ Eriksson's) or a Frost's #780 clipper (for 9-10$ and at way over 60RC, they're VERY hard to beat). Swamp Rat knives with modified edge would be even better. They're tough as nails (and warranty is unbeatable).

3 - Backup.
Either just another Mora, or a good folder. Full flat ground, hard, tough steel, and reliable lock. Above all: tough moving parts. I like Benchmades, but honestly I mostly use Opinels.

Some general thoughts: I like a sharp back angle to scrape my firesteels. Of course, a comfy handle (without knuckle shapes or anything... just a good, soft yet allowing a good grip, oval handle) is a must on any knife/chopper.

Hope this helps...

Cheers,

David