If you get a better signal from Rogers, get Speakout. Things you can do on a browser, works with Speakout. As an example, I use Google Voice for SMS, that saves $10 a month. Gmail for mail, Meebo or Ebuddy for messaging, etc. Anything that uses ports other than http and https port 80 will not work.

250 MB does not last long. I much prefer hobbled unlimited browsing. But the most important thing is how good your signal is! That is the biggest consideration, IMHO.

As for a SIM, apparently you can talk to a Speakout CSR, and they will mail you, or your 7-11 store for $25

It hasn't. You need to register using an American IP address, and have an American number. Hotspot shield and voxox can help you there. An Amerifriend works also. After you register, Google does not hassle you on where you live after registration.

the 403 area code is no good when it comes to registration. You need an US number. However, Google allowed an exception (on purpose of mistake, I am not sure) that allows calls to your Google Voice US number to forward to Calgary 403 numbers Great if you have a Calgary number. Fortunately, a Canadian VoIP provider, Freephoneline.ca offers free Canadian numbers, Calgary being one area. Even better, you can forward those numbers to most city centers in Canada.

If you get it setup, and live in Toronto as an example, the forwarding works like this. Someone calls your US Google Voice number, which is forwarded to your Calgary Freephoneline number, Freephoneline forwards to your Toronto number. Fun eh? You can set up Google voice to do jajah type calls, which is great if you have a phone plan that has unlimited incoming calls.

Voice quality is not 100%. Google Voice calls tend to be laggy, But it is free and it works. The freephioneline leg seems to work well though.

I found more use out of the SMS part of Google voice myself.