I've been using fizz for 4 or so years.
They use Videotrons network. You're covered well in the Ottawa area. Elsewhere in Canada you roam on the other carriers, but you're able to use your plan as you always would. You only get charged more if you roam more than you're at home for 3 months in a row.
Overall I'm very happy with the service. Data rollover is such an amazing thing.
As you should, but that's attempting to solve a different environmentally devistating issue.