Unlocking the Nokia Lumia 521 T-Mobile
I bought this Lumia 521 for only $65 on eBay, and is in working condition, everything is good and functional... except for the SIM lock, so i made the unlock order from a respected web dedicated to unlock phones and Cellunlocker.net just got the unlock code for the Lumia 521, i made business with them about 3 times with no problems, so i can say is a quite reliable service.
The unlock code consist about 20 numbers, very large compare to regular 8-10 numbers unlock codes of my previous phones, the unlock code cost $40 for the Lumia 521 but unlocks to any carrier in the world. If you just own a Lumia 520-521 keep in mind there is a series of updates know as Amber and GDR2, that will enable FM radio, Data Sense for the Lumia 521, new features and many fixes.
The updates will take time because the files are large, so be patient.