28ga and 3/4 oz of #6 or #7.5 @ 1200fps is my preferred load
I use a skeet choke, works like magic!
I roll my own but if you're not reloading, choose the brand your gun likes the best. The only way to tell is by buying a box and patterning it (ie: shoot a clean target that is big enough to contain the shot pattern) and with the choke you're going to hunt with - at the distance you expect to shoot them at. If you don't like the pattern, buy another box and try again. Get to know your gun and how it performs at different distances with a given load. Doing this will let you know the point of impact (POI) of your shotgun - your test results might surprise you!
Good luck! SD