BEARKLR: Well, it all depends on what you have now, what your setup is, how well the old bow is tuned etc etc etc. It's interesting that in "THE OLD DAYS" we always saught to have a 11-14% FOC. Then along came the speed freaks and the target shooters etc etc and everyone started saying you only needed 6 or 7 or 8 at most for great flight, lighter arrow, faster speed, more room for error in range guessing. NOW here this add comes back and tells you all the advantages of a heavier FOC. Nyuck Nyuck Nyuck.... Well, some of us have just stayed with 13 or 14 % for years and these things won't do a thing for me.