Bobby U won't shoot 20 ga in any 12 ga allowed event, to him it seems like an intentional handicap. We can all point to others at his level who do shoot 20 in 12 ga events.
Likewise, many of us has seen some great doubles shooters, like Waynes Mayes, I believe Kirkman, Hayes Hauford, Bobby D., etc who shoot autos for doubles and 12 ga. At the same time, many like Todd B and Bobby U do not switch guns.
I am not even close to being in the same category as these guys, but I gave up trying to shoot an auto in 12 ga allowed events for the reason SS pointed out, I just don't switch guns well. Also, my Kolar at 10lb 4 oz with a perfect fit just does not bother me with respect to recoil. Neither does a K80 at 9 lb 14 oz I recently purchased. I know others who come out to the range with a different gun every week and they never miss a beat and still others for whom no gun in the world is soft enough for them to want to shoot 1 1/8 12 ga.
This is all in the area of person decisions and nobody else can tell you what will work best for you.
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