I'm in no way a Wind fan, but to their credit, the European roaming package worked very well for us.
I called and added the option the day they announced it and went to get my SIMs replaced a few days later. Over a ten day trip through Europe we put about 330 in/out minutes and 15MB of Blackberry data between two phones... Not a single issue.
Make sure you activate both the $8 roaming option but also international roaming. They are separate SOCs.
Mobile phones: iPhone 5, Blackberry 9900, Nexus S, Samsung S3322 duos
Mobile data cards: Huawei E587u-5, Huawei E583c, Huawei E160
Postpaid SIMs: CA: Fido, Wind; INTL: Telna
Prepaid SIMs: DE: Fonic, Lidl; AT: yesss!, bob; UK: O2; US: AT&T; RO: Orange, Vodafone; FR: b&you, Lycamobile; NL: Lycamobile; BE: Lycamobile, Jim Mobile; CL: Entel; MX: Telcel; INTL: eKit Blue, eKit Yellow
Dead SIMs: too many to list