I have 2 phones here, a SwissCom from work and a Yallo pay as you go that I got when I first moved here. I keep the Yallo one for the cheap international texting although use my work phone alot... and I text to Canada most days.

My personal experience is that if the person you are texting is with Rogers.... no problem. The people at home who have Bell, well its another story, some go through some dont, and it has been this way for the past 2 years.

I would get your friends in Canada to check with their provider because my experience tells me that it is probably on their end.