from testing for nearly 30 years chokes and aftermarket chokes, most except Briley and Teague cheat on constriction. Most aftermarket cheat with a few thousand tighter. Some like Muller label them with numbers. in my last test of Muller 2 (supposed to be LM) and Beretta flush Optima HP chokes, the Beretta had an more even pattern with less holes in the middle. Buy one and pattern your ammo with the aftermarket versus factory. Then put it up for sale on the American sporting clay forum. It will be sold within a day. They are so gullible!
Henry