Is there really any other gauge? I have been using the 28 for all my upland hunting now for at least five years, I also use it for occasional trap sessions at the club. I don't regret leaving the 12 at home at all. I hunt over two wonderful pointers, and chasing them over hill and dale makes me really appreciate the lightweight and fast handling characteristics of my little Savage Milano over and under.
For ammo I really like the Winchester AA in a 3/4 oz load with 7.5 shot for almost all my hunting. I also reload my own ammo, and while I do have a couple of different loads, I usually try to duplicate the Winchester loads because they work so well for me out of my little Savage. I tried some Remington STS Premier, and while I find they work great for woodcock, I find the smaller shot these are usually available in a little too small for grouse and pheasant. Plus the hulls are not nearly as easily reloaded with my MEC 600 JR as the AA hulls are so I have avoided them of late.
I am headed out this weekend for my last hunt of the year for grouse, cant wait to light up the Milano one more time before heading to the club for trap!