My letter to the CEO of Virgin Mobile paid off, although it took them two months to respond. I got a voicemail message from a woman there apologizing for the way my problem was handled and letting me know that she was sending me a new phone and putting a $10 credit on my account to compensate me for the inconvenience. Actually, a postcard notifying me about the $10 credit and an email message notifying me that the new phone had been shipped both came before the voicemail message.
They even sent a better phone than the one we had originally bought. The original phone was a Marbl, their cheapest one (for which they now charge $9.99, although we paid more for it), and they sent an ARC ($49.99).
And, best of all, wonder of wonders, the new phone actually holds a charge for more than a few minutes.
And so, although I’m sure their front-line customer service still sucks, we’re going to stick with them, at least for the time being, since they have successfully responded to my complaint and resolved it in the way I demanded.