Find a good fixed blade that has a good curve on the blade. Keep it sharp, and have a honing rod with you.
The concept of the replaceable blade knives is cool, and they definitely work, but to me there is nothing better than something like the Old Timer Sharpfingers. The newer mfg ones from Schrade aren't as good from what I have heard, but a lot of good knife makers make quality designs that copy the layout.
Here is the one I have carried for about 20 years (the sheath blew out on me a few years ago during an elk hunt, so forgive the duct tape). Similar profile to the sharpfingers, but scaled up and with a much heavier handle.