Why get tied to a specific provider for UMA when you can pretty much use VoIP wherever there is Wifi?
Fido offers their UNO option (which is UMA) for $10 or $15 a month, unlimited local calls, using your home or work Wifi.
You can EASILY get unlimited calls to North America for less than that, additionally you can get a Pay As You Go account with most VoIP providers, usually calls to North America are around 1~2 cents plus you get way better international rates.