Generally applying inland is a lot slower than applying outland. Check the processing times....
I just looked and what's posted for inland processing times is a little deceiving... it LOOKS like it should only take 16 months in total but if you notice is says "currently working on applications received on july 8 2013" so there is a backlog there of about 9 months. Sooo. 9 + 16 is 25 months (ish) for inland. And outland you can choose New York...30 months or LA...26 months. So I guess just flip a coin or something. lmao.
Keeping in mind of course that unless you have a work permit you can't work in Canada while it's processing, whereas you could go back to the US and work while it processed outland.
Regardless of what you choose, when you initially mail your application you send it to mississagua, ont. They give the address in the application guide.