Canada Post has it's place. They aren't the cheapest or the most efficient but I'll still continue to use them for certain things.
One thing I have to say for Canada Post over the competitor is that they have pickup locations everywhere! In the larger cities, there should be an outlet within walking distance of your home. All our residential shipments are CP unless otherwise requested by the customer. There are no options on our web site for other couriers even though we deal with Canpar, UPS/DHL (domestic and international) and a local same day courier.
Everything we ship requires a signature. With Canada Post it's about $1 (or $1.50 can't remember) that we apply to every package. The problem with the other companies is that if there is no one to sign for the package, it gets returned to the depot which for the most part are far and few between. There have been instances where customers weren't home for the delivery and had to travel further to get to the Canpar pickup location than they would have to if they had just picked it up from us directly.
Not all couriers will make 2nd attempts at a delivery, and if they say they do, then they fake it! Canada Post use to and I hated it as it delayed me getting my goods by another day. Currently with their system, I can track it and go pick it up at the outlet on my way home without even getting the missed delivery pickup card first.