I use both O/U's and auto's depending on the situation. If you hunt where the birds are few it doesn't make much difference. However, have you ever downed a bird with the 1st shot of your O/U, and then mass qty's. of birds get up while you are reploading the bottom barrel? If you are extremely lucky you may get off one more round before the birds are all out of range. With an auto, you will always be on standby with 2-4 rounds at the ready......................