I can strongly recommend the auto. I am a huge fan of pump guns, but for large quamtity bird hunting you cannot beat an auto. Two experiences:
1/ We do a lot of pigeon shooting over grain fields for farmers. Last "Pigeon Fest" we shot about 600 birds in a morning. I was using my 1100 to reduce recoil, but also you do need that quick second shot, when 15 birds come in low and fast. If you are in a blind, you do need to be wary of your mates as the get a bit irritated by being hit by 12 gauge shells in the noggin all day.
2/ Every weekend for the past month I have been bird shooting in a vineyard. On a typical day we will let go 250 rounds of 12 gauge each. When the birds come in low and fast, skimming the vies, you need the auto. I used my Wingmaster one, but let it go after that, and stuck with the 1100.
You need the quick second shot ( or 5th as occurred this weekend ) and its great for avoiding a sore shoulder. Go for the auto.
Currently...Sako TRG 22, Model 29 .44 Magnum, Beretta M9 9mm, Beretta Neos, Colt AR 15 x 2, VQ 17 M2, Anchutze .22 hornet, the ultimate 10/22, LOTS of M1 Carbines.
"Beware of the Man with one gun...he probably isnt into guns enough to be safe with it".