That depends on when you ask. I can tell you that at present, the processing time differs very little from one place to another.
It is a two-step process, whether you are talking about sponsorship or naturalization. Parents who apply for naturalization must first apply to our citizenship office in Sydney. The second step in the process takes place at the embassy abroad. Sponsorships go through our usual sponsorship process, which is handled by our office in Mississauga.
In terms of processing, if someone were to ask me whether one way is better than the other, I would say there is not much difference.