If you need international calling card

[vikochka]

I use Tel3advantage Make Domestic or International Calls for Less
to make calls form home or cell phone. Good rates and quality. No PIN,tax,fees. Bonus on sign up. I using it for more than a year so if you have questions I can answer here

[messenger]

you should try www.click4prepaid.com

they offer great rates and quality, and no connection fees.

they also offer international callback which lets international callers to access cheaper US rates.

learn more about here:
www.click4callback.com

[kerv50]

I use http://www.SupremePhoneCards.com . Works great for me and my friends!

[Travel_addicted]

I've checked the sites you provided, but after doing some more research I decide to stay with CallinEurope. The rates they offer look more competitive compared to few sources I verified. And I won't have to pay any monthly fees and will be able to reroute my US number.