Nobody here can meter you constantly to give you the better deal that suits your usage patterns. That's where it's tricky to determine.
I still see wifi as an easy solution when traveling on modest data plans. YMMV.
I presently spend about 7 days/month in Montréal, Canada, though I live full-time in Connecticut. As a result of this, I need a really good Canada roaming service, which is why I am on T-Mobile's Simple Choice North America plan. I have three lines on that plan, with mine having unlimited LTE data. The coverage is amazing in Canada, because I have unlimited Bell LTE, but while I'm in the US, my primary place of residence, T-Mobile LTE coverage is terrible compared to my old Verizon service. As a result, I'm considering one of the following changes:
1. Separating my line from the other two, and putting it on the $60/mo AT&T GoPhone plan that includes 4GB of data roaming. Problem: I would probably exceed 4GB in the US, so I'd have to control myself. Cost: $60 for me, $75 for the other lines.
2. Bringing all three lines to Verizon and paying $30/mo extra for the Canada packages I would need. Problem: this is expensive. Cost: $160 (with our discount)
We currently pay $115/month with T-Mobile, which is why I'm hesitant to change.
I would really appreciate any opinions/advice on this complex issue lol. Thanks a lot, everyone!