Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
From what I heard most of the refurb iphones are returned phones when customers are not satisfy with it. $250 compare to $400 just for the packages is well worth it.

The warranty is not the same. Apple's warranty starts when the iphone was first activated and apple doesn't reset the warranty, so you have no idea how long you still have. Second ATT only offers 90 day warranty the last time I signed a contract with them, but unsure for now.
 
Apple will give you the full one year warranty for the att refurbished iPhones. You just have to send them proof of purchase and they'll adjust the warranty start date to the date you bought it.

They already hashed this out on the other $249 iPhone threads.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.