I have a .570 Nitride Jebs I may let go. I got a deal on an Indian Creek .570 and a Sumtoy .562 but haven't had a chance to shoot them yet. I also have a new, non-ported Carlson's .575  for sale in the 20 gauge choke section that other members on here  have had great success with? I didn't shoot it because I thought it would be hard to beat the .570 Jebs pattern, and may be a waste of ammo.