Ill start w/the disclaimer again that I like toying w/hi-performance, hi-priced knives as much as anyone on this list; and when I can pull the cash together, Im willing to put it into a good knife.
Knives can indeed become quite specialized and, on this forum, we cherish the *particular* strengths or unique characteristics of a given make and model. But when we say survival knife for a bug-out-bag, presumably were looking for a knife which is, above all, *versatile.* I.e., it can perform all or most tasks effectively, even if it sacrifices superior performance in some areas in order to ensure it doesnt fail in any one area. After all, isnt an emergency or survival situation precisely one whose conditions you cannot fully predict or anticipate beforehand? Even in the pleasantville environment of So Calif where I live, one can drive thru damp, foggy, 55F coastal areas in the morning; arid 85F-100+F desert w/little vegetation in the day; and end up in hilly, wet dense brush terrain in the evening. Sure, you can plan for various scenarios -- and, as usefully noted by not2sharp, cliff, and others, youd better -- but precisely because you cannot know which *one* scenario you may be in before the fact, you need a *versatile* knife.
OK, I suppose if I could afford a second ATAK, it would make a nice knife for the car trunk. But as not2sharp et al thoughtfully show, survival is a way of thinking and preparing which you bring to your knife (and whatever else you have), *not* a set of properties or skills which your knife bestows on you. If youve prepared beforehand, then you should be able to make do just as fine w/an Ontario, Cold Steel, or Kar-Bar as you would w/an equivalent-sized Busse, Mad Dog, Simonich, etc. A bug-out bag is, by its nature, something composed by your knowledge, experience, and foresight, and *no* amount of money trumps or supplants that.
Two of you are in a survival situation, and you are incapacitated w/two broken arms. Who would you rather be with? The prepared individual w/a 4 Spec Plus Parachutist, or the idiot w/the 12 Mad Dog Dragonslayer? If you cannot survive w/a Kar-Bar, having a Busse will not boost your chances, at all.
(yadda, yadda...)
Glen
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The piano has been drinking -Tom Waits