Hi Gary, yes it is a fact that saws destined for Canada are somewhat stronger than in other countries ie., bigger cranks, thicker casings and larger mufflers etc., but I think it's done deliberately, much to the advantage of the United States, because they end up with most of our top grade timber anyway, so the joke really is on us because Canada isnt big on remanufacture, but rather prefers to sell their wood in the roundwood form. Some models of Stihl and Husky that are released by the NLAP here in Canada have a lifetime gaurantee.
Hope this helps,
John