I use a Kick's Gobblin' Thunder with a .675 (I think) restriction out of my Benelli with Winchester Supreme High Velocity #5s. I've shot my last 3 toms with this set up and they've never so much as flapped a wing. They were stone cold DRT (Dead Right There!) as soon as I pulled the trigger.
"Knowing when to shoot and when to wait is one sign of maturity in a bowhunter. Be patient and pick your aim point carefully." ~ Randy Ulmer
"I suppose it's the way of hunters. We are very odd fellows." ~ Peter Hathaway Capstick