It's more of an individual preference. I ordered it 4 times - after sponsor approval, file transfer, when we received a document request and submitted what was asked. Once PR is issued, I will order one last time just to see what the officers had to say.
Did you also want to know how to order notes if you are outside Canada? If so, you need someone in Canada (e.g. Canadian citizen, PR, or someone with a valid work/study permit or visitor visa) to apply on your behalf.