Not sure how the data works, but I can tell you that the Microsoft store is extremely generous. The employees are a lot more helpful and friendly, unlike the stuck-up apple employees. My mom had the HTC radar for about six months, and there were lots of problems with it- so when the Lumia 920 and Windows 8X came out they gave her a free one(she chose 8X). It just about last week here calender would not work so they just gave her another phone.
Unfortunately its only the stores that are good: tech support is awful...
Wilson 6.1 95 16/18 Solinco Tour Bite 17 @ 55