That's exactly why everybody should pattern their own gun with their own load. I've patterned three different turkey choke tubes in two different guns and tree different barrels. I used the same Federal Premium, 3", #4 Buck loads in all of them. All three of the turkey choke tubes blew my patterns apart. The extra full and full choke tubes weren't much better. The modified and improved modified tubes weren't too bad and I'd use either one of them if I was limited to a factory tube. The improved cylinder tubes were just so so with #4 buck, but shot pretty well with 00-buck. The factory Pattern-Master wasn't too bad, but I thought it could be better. I called the man that makes the tubes and told him what I what to shoot and my intended load, expected range, etc. He open up a regular Patter-Master tube and it has been the best patterning tube with #4 buck yet. Everybody's gun and load may shoot differently. That's why it is a MUST to pattern each load and gun. What works for me, may not work for you. I know many people will shoot a load and choke combination because their buddy does, but unless he patterns his gun, load and choke combination he'll never really KNOW what works best for him. I doubt if many people actually spend time patterning their shotguns. Can you imagine doing that with a rifle?
Oh, edited to add this: I also have an Under-Taker Coyote Killer choke tube. It shot as well as the off the shelf Pattern-Master and cost alot less.