It is a shame you are not over here. If you check out the Pigeonwatch site in the for sales column a composed pair of AYA number 2s sold for 900. 450 each to separate owners who were both delighted and described them as sleepers. I picked up an as new AYA number 3 three inch magnum for 300 early this year and the owner was also selling a number 2 in immaculate condition for 450. All 12 bore.
I have owned a number 4 and for a long time it was my only gun. It was a 28 inch barrelled gun and a delight, the 26 inch barrelled number 4 I once shotI seemed clubby and ill balanced as did a number 2 in 26 inch, but that was only an individual gun in each case. Curiously I found the xxv boxlock and sidelock models to both balance well. I admit it is pretty subjective and based on few examples over a long period of time but as has been said buy the gun as from my experience the balance and feel can vary between models and barrel length.
I wasnt tempted to buy the number 2 in 26 inch barrel I handled for 450 bargain that it was because for me it just didnt feel right. However if I was considering buying another AYA I would be looking for a xxv sidelock or boxlock that came up to the shoulder well and be looking for a private sale as some trade prices are still very high.