Gotta agree with the Plainsman here and like I said when I replied to the same post in the general forum: for extended backpacking, GO LIGHT!. Colin Fletcher, the Dean of Backpackers, usually takes either a lightweight (6 oz) sheath knife or an SAK! The first time you get a splinter, you will really appreciate the tweezers on an SAK.
I DO like to have a fixed blade handy, so it's usually something like a puukko. They are very light and serviceable.
Here is my favorite bacpacking combination: a leatherman (with the pulse now being my favorite, replacing the original for backpacking), an SAK Rambler (small SAK), and a Grohmann Camper (or puukko).
The big disadvantage with this combo is that there is no saw. Therefore, a lightweight Opinel Saw is an option (3 oz), or replace the pulse with a Leatherman Supertool or Wave, the Wave being the lighter and more versatile of the two--each has a saw blade. You can also make your own lightweight saw like the following:
http://www.primitiveways.com/tools.html
and I've seen similar light weight wood saws in the hardware section of many dept stores. Hiking maintained trails does not require a lot of chopping, but if you want to craft a walking stick or make poles for a tarp, a saw will be handy.
But in general, I can't imagine carrying a battle mistress or a khukri or other big knife on a backpacking trip unless my goal is to do camp "primitively" or explore survival techniques. If that's the case, then any number of big knives would do for you. To save money, I'd look at the Becker line. If money is no object, buy a Busse SteelHeart or Battle Mistress or a custom knife like Trace Rinaldi's awesome Armageddon.
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Hoodoo
I get some pleasure from finding a relentlessly peaceful use for a combative looking knife.
JKM