Well over 6 months in and freedompop is still working for me and has only cost me $31.20(20 was to port my number to google voice to allow me to use it for voicemail) to get it all set up correctly. Hoping the free plan will last a while longer in the US as I'm definitely enjoying not having that extra monthly bill anymore, but they did cancel their free plan for European customers recently so who knows how much longer the US version will hold up.
As for the service it's worked just fine to enable me to do some light messaging using cellular data while saving any heavy use for wifi. You might not have as great a service if you need to call/be called a lot while not on wifi as that hasn't been completely flawless, but I do most my calling while on wifi with VOIP apps.
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