I am in the exact same boat as you are, tcomp2. The thing about the variation is pretty accurate which makes it frustrating to have a clue. However, what I would suggest is to read OTHER people's timelines at http://www.canadavisa.com/canada-immigr ... ship-b5.0/
. Then you at least have something to make a comparison against.
The most consistent thing seems to be that they will tell you if the sponsorship is turned down or approved (I've never read about anyone being turned down though) one month after they receive the application. After studying the sponsor that they would turn their attention to the person being sponsored and the genuineness of the relationship. The file then goes to the visa office, which I'm assuming in your case is Buffalo. Needless to say, it's the proof of the relationship that is the most important variable.
Assuming you don't have any problems in your application everything could take toward the lower end of the scale (the 4 or so months). I sure hope so for you and me both.
I would disagree with giuseppenero that finances are among the top things to worry about in the process. I don't know for sure about the other provinces but for Quebec if you are sponsoring a spouse and not a child, you don't have to prove you are able to financially support them. They do ask if you're on state benefits or if you've not been able to pay back something to the state though. The "burden" on the state he mentioned comes in to play more, I think, for the medical checkup. I think you would have to have a medical serious condition for that to be the deciding factor though.