That rep was blowing smoke out of his house. There's no difference in the post-paid and the pre-paid network. The only difference is the type of account. The go phone still uses an at&t sim.
You shouldve asked that rep the go phone uses what network as opposed to at&t. That rep probably just wanted to talk you out of their pre-paid plans and into the regular plan. After all they make the money by signing you up for a contract.
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