Well, I think of changing my mind about not returning it. The problem is the unlock situation. I am traveling abroad in a month and it seems like there won't be an unlock for AT&T version for a while..
If I do return, I will just replace it will European Lumia 900.
You can return it and just buy and unlocked rogers version for $589 USD. Probably be a lot cheaper than the european version b/c of exchange rates