I bought it back in February. There were two motivating factors at play; my Nexus 4 had become unreliable, and I was taken-in by the One+ One’s combination of reasonable price, flagship specs and limited availability.
Last month we made our annual trek to the Great White North. While making plans an associate, who is also a T-Mobile customer, recommended that I call T-Mobile and make sure that we had the correct plan. Failure to do so would result in us incurring the usual roaming charges for platinum-plated voice and data service while travelling.
On the very eve of our departure I remembered to call T-Mobile and make the change to the account. In fact, I called from the airport (IAH) while we were awaiting the departure of our initial flight to Toronto.
Of course, I called the from my mobile phone. The automated system advised that there would be some on-hold time, and I could opt to have them call me back, which I did. The callback took about ten minutes.