Has anyone used Best Buy to trade in a device in the past? did the Best Buy trade in of my M1 when buying the M4. I noticed it stated after receipt of trade in in store it could take 7 days to update my total cost. Not a big deal. BUT, wondering i can keep my M1 home for a day or two to make sure i want to keep the M4 before trading it in and then I have none if i decide to return the M4. Does that make sense? I guess i can call BB support but figured I would inquire here first. Thanks!