I've come to believe there isn't a perfect survival knife, because survival isn't perfect. There are too many variables to consider. I think most of us instantly think "wilderness survival" when this topic is broached, but in realty survival can be required any where and at any time.

This leads me to think we all need two layers of knives:

Everywhere Everyday Carry (EEC) = Stout 3-1/2 to 4" folder or skeleton necker type fixed blade

Durable Fixed Blade (DFB) = 5 to 8" fixed blade.

I use to preach the Trifecta concept, but have been shifting toward "lighter is better" (allows you to move swiftly and more safely). This means the selection of the DFB is more difficult, because I favor a 5" knife AND 8" knife.

I've encountered field tasks that are impossible for a 5" and nearly impossible for an 8".

Ultimately, for now I've settled on a Swamp Warden and NMSFNO.

My wife uses a Spyderco Endura4 FFG and a Skinny ASH.

I have a RMD on my "fighting belt", but might ditch it if I have wear my emergency ruck containing the other two knives.