I am a Canadian. I prepaid $20. I got great customer support. I was traveling and using this app I called a mobile phone in Austria from Geneva Switzerland using my iPhone for 6 minutes and it cost me about 30¢ and voice quality was great. But remember that you can only call from wifi. I also called back to Canada. It cost less than 1cent per minute. But on some calls the voice quality is a bit lower so get a strong wifi signal if you can. I still have over17$ credit that I will use traveling in a few weeks.
VStarr about RoamAside, v1.7.3