The Bucks are made with 420HC steel, which in my mind is marginal at best assuming excellent heat treatment. Some of the Case knives are made with better steel, but I'll be darned if I can find which ones are which with a quick google search.
If you go to the agrussell knife site (and some others) you can find similar knives to the ones you're looking at, made with better steel and only a few dollars more. The Boker Air Force Pilot knife has a 4.5" blade and is a modified clip point just like the Buck and Case knives, but it's made from SK5 steel. It should take a keener edge and be easier to sharpen. It's the same price as the Buck