I was wanting a new 12 Gauge Montefeltro Silver but they only come with a 28 inch barrel. I have always preferred a 26 inch simply because they were an ounce or 2 lighter and just liked a short gun. Felt like I could get on a bird quicker. Maybe I am all wrong. Tell my why I should by a gun with a 28 inch barrel over a 26?
You don't. The longer the barrel the better the sight plane. What's more important than barrel length is your choke. I have a 26" barrel on my duck gun with an aftermarket Carlson choke tube. Much, much better than factory chokes and far better patterns which = more dead birds.