Personally, for all the clay target games --- I prefer an O/U.
But again it comes down to Fit - and budget. To score your best - you have to have a gun that "Fits" so it hits where you look.
O/U has an advantage - you can put in 2 different chokes. If you re-load then you aren't having to pick up your hulls ( shake water and or crud out of them ). Mechanically, an O/U is a lot more reliable - it isn't as fussy about shells ( if you can get the shell into the chamber and close the gun it'll fire ). Some semi-autos are finnicky - and there are way more parts in a semi-auto than an O/U.
O/U's can fail - break springs, firing pins, etc - you have to maintain them like any shotgun.
Adjustability - and fit in all seasons is an issue on any sporting clays gun. It has to have the same point of impact if you shoot in a T shirt on a hot July tournament / or on a cold day in November. That means - most angled comb guns are out - because you'll move up or back on the comb on hot vs cold days - based on what you're wearing.
For parallel comb guns / where the comb is parallel to the rib --- Browning makes a couple of guns ... Citori XS Skeet model, Citori XS Special model. Either gun will work for you / my personal preference is Citori XS Skeet, with the adj comb, 30" barrels --- but new that gun is in the $ 2,900 range...
I primarily like the XS Skeet model - because with its built in adjustability it seems to fit 99.9% of the shooters I see. Its also a work horse / and a solid long term investment - if you take care of it ( often selling used for as much as you paid for it in a few years ) - even if you've put 100,000 shells thru it.
Durability is an issue on sporting guns - because many shooters will put 40 boxes a week thru their guns easily with weekend shoots and practice - or at least 12,000 shells a yr thru a gun / and many put 25,000 a yr thru them.
A semi-auto like the Benelli Super Sport model - has a lot of adjustability with shims, snap in comb pads, snap in recoil pads to set it up properly ...and new its in the $ 1,875 range.
Angled comb guns - whether they are marked for "sporting" or "field" or whatever ...are poor choices in the clay target games in general - because of Fit issues. Guns like the Browning Citori, 625 Sporting as an example - or the Citori Lightning - are very durable guns .... but they might give you fit issues ...