Okay, understood. Thanks for your input.Yes, just enroll to that 5$ north america roaming. It should be enough. If you are on postpaid, it will be more cost while roaming without this roaming plan. Also make sure after 2 days of activating the plan, call them back and verify if you have roaming plan enabled. Sometimes at the store they dont do it correctly and end up paying for roaming.
Call: As its unlimited, you can use your phone network.
Data: As its limited, try to use less while outside of home.
Rest should be fine to use it for years. No issues for the last 4 years.
Another question is have you investigated Google Fi option instead of T-mobile? The plan rate is better than T-mob, and it essentially allows unlimited international roaming without the need to think anything about line termination. Just wondering if Google Fi has a compelling disadvantage over T-mobile, especially while living in Canada, yet maintaining US number.
Thank you.