Pretty much any Spyderco folder would be good on fruit. Any steel Spyderco uses would be just fine, though you would want to clean Superblue pretty soon after using. My personal favorites would be the Military, Caly 3.5 and Para 2, because those are knives I happen to own. I have a few Salts, too. They are also great--I prefer the serrated versions, but the saber grind on the Salt series does not slice as well as the FFG blades.