Jeff, I went to a high FOC setup last year and was amazed at how hard my arrows hit, and actually to me I got better arrow flight. My arrows had an FOC of almost 22%. You honestly only see the benefits of the high FOC setup once you get to about 19% FOC. Trust me you can hear the difference when your arrow hits. It really packs a punch. The person to talk to about high FOC arrows is Aussieguy, he's the one who got me onto them.

Gold Tip has a FOC calculator on their site and you may want to go read the reports by Dr. Ed Ashby. They can be found on the Tradgang website. He does some great reports on broadheads and high FOC setups.