I would go with a newer model rather than the Ithaca. Not that the Ithaca is a bad gun by any stretch of the imagination, it does the same thing that a Reminton or a Mossberg is going to do... but if your budget is up in the $600's a Model 870 Reminton is totally in your means and is great shotgun. Mossberg has the 590 security model and that has praise sung as well.
They each fit a different niche. I guarantee the Ithaca is going to earn you a few more looks, but as far as practicality and accessibility to customer service and all that, Mossberg and Remington have it beat simply because you'd be getting it from a store and not from a friend.