I haven't even been able to register at all
And now they're facing the same kind of problems with the Galaxy Note 3 US$50 Google Play credit promo in the US, where bad people started generating valid IMEIs to claim the credit and now, the true owners of the IMEI are getting an error because their number has already been used.
In the case of the Note 10.1, as I understand it, was because the perks could be claimed just by going into the link without even having to buy the tablet (dumb Sammy...).