I have been using Fi in Canada for years and never had any issues. It works great

However, my Canadian friends sometimes ignore my calls because they look like SPAM, coming from the US.

Also, some government agencies are blocked from calling outside Canada.

Also, some Canadian 800 numbers can’t be called from US number.

All that is worthwhile because you can get calls from US banks and other security verifications and the cost is way less than any Canadian plan.

You can get free Canadian numbers to use on data from Fongo and others.