If you want to find a real sleeper check out Colonial. This old US make is still able to produce a good stockman for well under $10 dollars. Workmanship is much better than on the imports in that price range. Nothing Fancy - just a workman's knife.
As for the Colt AR15K, well we all have to start somewhere. Stay with the cheaper knives until you have figured out what you like, and then consider getting a good high quality example. There is nothing worst then dropping alot of money on the wrong knife.