Aloha,
Best of the best huh?,,,,hmmmm that opens up a lot of possibilities and opinions. Here is my 2 cents:
For productions folders....the Chris Reeve Sebenza just is hard to beat. Simple, ugly, hard to beat. The frame lock is simple, and bullet proof. Compare liner locks from the popular brands and with the Sebenza...its a no brainer which is better. The Sebenza also comes in a lefty version also, and will absolutely ruin a lefty knife owner for life.
Strider AR or GB. Strider now has the lock on bullet proof folders. It is way over built. It has a 4 inch blade that is 1/8 inch thick (I think) It is a liner lock, but locks with a solid "chunk" sound. It does fit in your pocket, but its a handfull. Both closed and open it makes those old big Bucks look like a sissy blade. Until the Busse guys come out with their folder, it leads the pack as far as hard use folders go.
Mayo TNT. Made by Tom Mayo here in Hawaii, (and who links this forum on his web site) TNT stands for Titanium N Talonite. He makes most of them with Stellite now. Handmade, they come wicked sharp (scary sharp in knife parlance) with the talonite/stellite blade and a titanium frame. These knives are also frame locks. Tom takes all the best features of the Sebenza, and improves it. Talonite and Stellite are non ferrous alloys...the advantage is that they do not and can not rust. Neither the blade or the frame (titanium). Mayo has several models from small to large with a variety of blade types. Expect a bit of a wait if you really want a custom. The fit and finish of Mayos knives are legend in the contemporary knife world.
Me, I have a big mix of knives. My daily carry is usually a Strider AR, a Chris Reeve Sebenza, sometimes a Microtech SOCOM or an Emerson. Hard use folders all.
I would advise you, and anyone who is interested to read Bladeforums.com, knifeforums.com or Usualsuspect.net There's opinions and lively discussions just as here in the AR15 forum. You can do a search of the sites for any of the knives mentioned or that you are interested in, or go to the specific forums for the brands you are interested in and get a consensus of opinions.
The Spydercos, Benchmades, Case, Bucks are all very good knives, and I have a bundle of them too. You asked for the best....and those that I have mentioned are a definite cut above the rest. It is up to you to decide what features you want and how you want to use it. For each of those factors....there is a knife for you out there.
Happy Hunting
wabi