I would go with .06 myself for the simple reason that around here you can shop any wallyworld & find at least 4 - if not 6 - different kinds of ammo for .06. Go to a gun/sporting goods store & find several others as well. 308 has only one or two choices. That was the main reason I ordered my Marlin XL7 in .06 - greater variety of cartridge over any other round. If .308 (or .270 for that matter) was more common than .06, I would have bought that instead. Yes I know that there's a great variety of .308 on the internet, but that's not the point. I want to be able to walk into any store that sells even a small amount of ammo & walk away with the load that shoots right in MY gun.