They are on sale for $69.00 off contract at the Microsoft store, looking at getting it as a back up phone on AT&T.
The 521 will work on at&t's network only if you get it unlocked first. Why not just buy the 520 (att&t's version) which is on sale at the Microsoft store for only $59.99, and you won't have to worry about getting it unlocked first.They are on sale for $69.00 off contract at the Microsoft store, looking at getting it as a back up phone on AT&T.
The 521 will work on at&t's network only if you get it unlocked first. Why not just buy the 520 (att&t's version) which is on sale at the Microsoft store for only $59.99, and you won't have to worry about getting it unlocked first.