CRKT offers some very good quality knives, but beware their chisel grind knives. They're very difficult to cut with because the bevel is at the wrong angle to the cutting plane (if you're right handed). They also tend to be heavy. One of my favorite CRKTs is the M21-04, which is a beautiful spear point. Their titanium tantos are very nice too and are double grind, but again, a bit heavy when compared to G10 and FRN handle knives. Kershaw, too, is excellent.
I'm a great fan of Cold Steel knives. Its Trailmaster fixed blade knife is a classic and the new Voyagers are Recon 1 folders, with their Tri-Ad locks, are the strongest in the world. The Voyager features clip point, Vaquero, and Tanto blade configurations. The blades also go up to 5.5 inches, which are monsters. The 4-inch may be ideal. If so, the Recon 1 might be the way to go. The clip point and Vaquero blades are flat grind and the tantos are a nice hollow grind with a thick spine that makes them great for prying and batoning.
Finally, Spyderco Enduras, Military, and Police models are outstanding. Many like the VG10 steel, which has excellent edge retention and anti-corrosion properties. These can start at about $55 and go up to more than a hundred. The new Endura 4 FRNs come in varying colors and with nice flat grind blades that can whittle wood or slice tomatoes. Me, I'm not a huge fan of flat grind knives, but I have nothing against them, either. Since people who know much more than I do about knives love them, I defer to their greater knowledge and experience.
Again, take a look at the Cold Steel Trailmaster. Look up some reviews on YouTube. Also, do a search on the other knives recommended in this thread. I've seen many good reviews there.