While I like browning, my buddy has a Special purpose turkey gun in 870 mag and it's a nice gun. Comes with screw in chokes so you can pretty much do anything you want with it. He did get a cantilever deer barrel for it though. It's driving him nuts that it's not camo though.

And barrel length really doesn't have that much to do with performance or patterns. Most modern loads will burn all the powder in any conventional length barrel. It has more to do with how the over all gun feels and swings when you shoot it. If you plan on hunting in heavy cover or where you need to get the gun up really fast you might prefer a shorter barrel than a longer one. My A-5 stalker only has a 21 in barrel on it and I really like it.

Paul