I can't speak for the gamekings because I've never used them. On the other hand I've shot the Sierra flat base Pro Hunter spritzers and the Speer Hot Cor spitzers for many years with great results on deer. My favorite two bullets for my 25.06 are the Sierra 117gr PH and the Speer 120gr Hot Cor. Both these bullets are very accurate in my rifle and their on game performance has been excellent for me. My daughter shoots the Sierra 120gr PH in her 260 and my son shoots the 150gr in his .308 with equal results.