Rather than taking a large knife for chopping, have you considered a folding saw? With the combination of a light folding saw and a knife around the S5's size, you can do an awful lot. You can split large logs with a small knife to baton, plus a couple of pre-carved wedges, and you can cut off pieces of fallen trees easily with a good folding saw. The saws also usually save a fair bit of both weight and energy compared to either a hatchet or a chopper-sized knife.