I shoot a 20 gauge at everything in the upland that is leagal to hunt. Here in Washington we have Valley Quail. I don't shoot dove. So I can tell you this; A 20 SxS is a great gun for quail. I have found 28 inch barrels will actually give you a quicker and smoother swing than a 26. Double triggers are better than a single. Quicker choke selection. Ejection is what ever you prefer either one works.

I set mine up this way for quail. 1st barrel Front trigger Improved Cylinder. 2nd barrel back trigger Light Modified. This set up gives me a good pattern close and far.

Shells I shoot regular 1200FPS Trap and Skeet loads. 7.5 or 8 shot your call which. They both will do the job

Like i said I shoot pheasant, chuker, quail and hun's all with my 20 no problem.