The Longbeards shoot tight to start with. In my 870 Special Purpose Magnum with a 26" barrel using a Jellyhead .660 choke the pattern at 15 yards is a little bigger than the size of baseball...pretty easy to miss, especially for a first time turkey hunter. With a Carlson .670 choke, the pattern opened up to about the size of volleyball and still has very good, even pattern at 40 yards.
My gun prefers the 3" shells over 3 1/2" shells. The 3 1/2's(any brand) always blow apart leaving big holes in the pattern. When shooting Longbeards, it likes 5's over 6's although there isn't a big difference in them. The 5's pattern is just a little more even.