Good question. From what I understand, carriers are not so concerned about the device manufacturer as they are with that device's hardware being compatible with that carrier's network. For example, although I can't cite the exact one, I was reading a thread on XDA where it said some Sprint phone versions of the Samsung Intercept are programmed to a different bandwith than Virgin Mobile's intercepts. That is why you want to be relatively certain any device you buy is compatible with the prepaid network, and perhaps the best way to do that is to search the web and verify it can be done. To save yourself the headache, I would highly recommend simply buying one of VM's supported devices, it makes things much easier.
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