To me, a fighting knife must be long enough to provide superior "reach"; sharp and heavy enough to cut through flesh and bone; and durable and easy to sharpen and maintain. So, that's why I like the Ontario Spec Plus line, and especially like the Ontario Spec Plus 6 fighter.
Not only is the blade of the knife razor sharp, but so is the top of the blade from the tip and then about 1/3rd of the way back. It is fast, easy to maintain, easy to grip and easy to sharpen. It has great reach, thrusting and cutting capabilities. And, it's priced right at about $45. Besides all that, it's also made of superior 1095 high carbon coated steel.