[M.T. Pockets]

I agree with getting the one with the modified barrel, I'm not familiar with the lengths between the full & modified, but don't worry if the modified is a couple inches shorter, you won't lose anything.

I'd be willing to bet that more steel shot goes through Remington 870 shotguns than any other shotgun in the world.

The choke systems mentioned above are a great option and a replacement barrel for an 870 is going to be less costly than most other brands. I find myself using modified about 80-90% of the time anyway so don't feel handi-capped if all you have is a modified barrel. I think there will be more and more steel shot requirements for all types of hunting.

Careful with steel shot when you're eating game, it really hurts the teeth.