Obviously, everyone has their own opinion. I shoot with a pump right now but am looking to upgrade. I have shot a 25 on skeet and a 24 on trap. This just shows that any repeating shotgun is plenty capable of breaking targets. From what I have seen, most of the really good shooters on the field are shooting o/u shotguns. I personally am torn between which to buy first, an o/u or an auto (I want both, as one can never have enough guns), although I am leaning toward the o/u.
Get whatever you like, either one will work just fine. Higher price, lower maintenance for an o/u. Lower price, higher maintenance for an auto.