In the process of switching over to CallCentric voip service. Very flexible pricing based on calling needs. Much cheaper than traditional POTS line. True that it depends on internet service but these days it does not matter with so many phones around.
With Callcentric you have phone service on your landline at home and same service on 2 mobile devices (in my case android and iphone). All devices calls out using the same line irresp of where i am. I can even use my account as a calling card. Callback service like what google voice used to support in canada via 403 area codes. The list goes on and on.
Can port canadian numbers. Porting take several days (versus 1-2 days in US) but that is because of archaic and red-taped canadian regulations and service models.
disclaimer- I don't work for any telcos or affiliated corporations. This is an unbiased report, your experience may vary