A No. 2 IMO but watch out for the weight of the gun. AYA's are mostly too heavy for their bore size. I was at Fieldsport last week and all his 28 bore AYA,s were too heavy (over 6 pounds) and too expensive at around $7K.
I have a No. 2, I purchased from Cabella's, a few years ago that was almost perfect, dimension-wise, for me. It weighs in at 5 lb. 7 oz., which is about what a 28 should weigh, IMO. I got it for a good negotiated price but the firing pins were bent, as I later found out. New heat treated pins from Jim Eyster, fixed that problem and it has been a flawless shooter since then.
Take your time and look around for the gun that fits your shooting dimensions and balances well and is priced right.
