Doesn't really matter but what shotgun will you be using? The reason I say it doesn't matter is because you can have the same two shotguns down to the barrel and one will group say Lightfields better and the other might like the Federal Barnes. I've been slug hunting for over 27 years so your best bet is to go buy a box of each or many different brandsand set up on a rifle rest and shoot for the best group. See how each preformout of your gun. You'll want to try for the tightest group. Scope or rifle sights?? You'll want to start at 25 yards and work from there. Sorry there is no magical way to just do it......just lots of shooting to find out which slug preforms the best out of your particular setup. Good Luck and get to practicing, time is getting short.