When it comes to airports of entry that I've used in various countries, Canadian airports are the ones where I've most often been sent to secondary. But the Canadian questions haven't been all as intensive as what I've sometimes been asked by US CBP in the baggage claim/post-baggage claim areas.
When it comes to the actual searches of my belongings, US CBP has been more intensive than their Canadian colleagues, at least at surface ports and airports of entry.