No I didn't, but we have friends from the UK spending the winter in Spain who call back to the UK several times a week on their UKcell phones and the cost is apparently very reasonable compared to what we see in North America. There is no need to swap out their UK sim for a Spanish one either. Now admittedly larger geographics may play into things here in North America and add to costs as well but you'd think with present technology that more cost effective data plans would be available. I'm thinking the big three (Rogers, Bell & Telus) can pretty well charge what they like, within CRTC guidelines of course.
We traveled across Canada in our motorhome last summer mostly on the Trans Canada Highway, and with our Telus plans never had cell phone service from about Moosamin, SK all the way to Sault Ste Marie, ON with the exception of some spotty service around Winnipeg. We find it unbelievable that a major Canadian cell phone provider can not guarantee cell phone coverage at least along the entire length of TCH. We travel south in the USA over the winter and anyone would be hard pressed to not receive a good cell phone signal on any of the interstate highways.
We don't use our iPhones in the USA at all because of the huge roaming rates, although the T Mobile option I read about on this thread does sound quite good, so we might check that out.
I am here: http://maps.google.com/maps?ll=28.381493,-81.675959