When I saw the rumored link between GR/Celtrek and Maxroam/Cubic posted(certainly logical because both use BE), I decided to try my Maxroam card that only had a very small balance on it (guessing 6 or 7 euro left). While it registered on AT&T USA, the balance check just came back with a zero euro balance. Was going to use up the rest of my balance on an upcoming trip but I guess that decision is made for me. Have plenty of other communication options.
Getting real tired of dead callback sim cards though. I've gone through travelfone, yackie, maxroam, um/riiing and um+. Really hoping the ekit simple calling card I got over ebay lasts longer....sixth time is a charm?

Phones/Wireless Devices: Doogee S90, Isatphone Pro, Amazon Kindle 3G, SkyRoam MiFi device, Karma MiFi device, AT&T Liberate MiFi device
Sim Cards: T-Mobile (Mint), AT&T (Mifi device or Kindle), Koko
Satphone: InMarSat
Broadband US Wireless Data: AT&T postpaid, Sprint (Karma Mobility prepaid)
Broadband International Data: SkyRoam
VOIP: Skype