In 2007 I bought a factory second RAT-3 in D2. It has been my project blade since. It got uncoated, blued, convexed (fun activity with D2). It has been on my belt for most of my wilderness/survival activities. I also have a Fiddleback Ladyfinger, but if it is going to get dirty I prefer the RAT (which is most of the time). RAT/ESEE and Fiddleback Forge knives are the most comfortable knives I have ever held by far.
Granted, it won't baton as much as a big blade, but personally I find the 5-8" range inconvenient for what I do. As other said, it all depends of your location. In the boreal forest, wherever you look you can find dead balsam fir or spruce. Up to 5-6 inches you can put them down simply by pushing, and lever them between strong living trees to break them. I keep a folding saw or a camp knife in my pack at camp, but mostly use my RAT-3. It is also borrowed a lot by other instructors, especially for dressing animals and scraping skin for tanning.
I am the one giving the lecture on knives at my survival school. Here is what I recommend for a bushcraft knife:
- Fixed blade, pivots are weak points.
- 3.5-4.5" blade (my preference for what I do, YMMV)
- No serrations. Combo edges affect carving abilities. Saws on the back affect batoning abilities. If you want a saw, buy a saw.
- Carbon/tool steel: Stainless tends to snap (I have seen it 3 times in the last month). Stainless can also rust (also seen recently).
- Watch out for high wear steel: They are a PITA to sharpen.
- Ideally, steel should be blued or coated. For a coating make sure it is "baked" and not painted on. Painted coating can flake. A patina is also a good solution.
- For carving, you want your hand as close to the blade as possible. So no guard. I love when there is a choil for the index.
- Handle material is a matter of preference, all I will say is that wood can shrink or expand and kirinite is slippery if your gloves are full of snow.
- Grinds are also a matter of personal preference. I prefer convex as the edge is tougher, but scandi is easier to sharpen.
This is my personal opinion and I won't be mad if anybody disagrees

My conclusions could be different in another environment.