Went to the range this morning with my brother to test our new tubes with buck shot. I used my 870 3", and he has a 870 3.5". We used Remington 00 buck. At 50 yards He was getting almost identical patterns with his modified choke as the pattern master. I used a full choke and got just a slightly tighter group with the pattern master. I was expecting way tighter groups. For $90 bucks a piece not sure if these tubes are worth keeping.