If you can get a wi-fi connection that has decent bandwidth you should be golden. Most people don't understand this new feature but it is basically using your cellular phone to place VOIP calls. From Sprint.com (
http://support.sprint.com/support/a...ing/173e331f-8423-453e-93cb-4688f6a91f67) the calls will either be free if calling back to the USA or will be subject to their normal long distance roaming rates if to foreign numbers. Have a great trip!