I think they all say that!

That said, I assume we're talking about fixed blade, outdoors knives here.

I've really always had knives around the 4 inch mark or less and, when looking at new knives, didn't really see the need to go much larger; I've never been in a situation where I thought I needed a bigger knife for the task at hand. That said, I do almost always have an axe and/or hatchet when I'm camping or backpacking.

As far as blade shape goes I like the drop-point and I also like my knife blade to be a bit on the thicker side for general purpose use. The extra thickness is, in my mind, an aspect that helps ensure your primary knife is a bit overbuilt for those just-in-case emergency scenarios (I'd prefer to wager on too thick than too thin here).

My newest blade is a modified drop-point with a length of 3.8" and a thickness of 0.18".