Summary: I bought one 3Gs from this page once, but from different seller. That one was faulty. I contacted Amazon, cause that was fulfilled by Amazon. I returned the phone. Amazon immediately gave my money back. Impressed! So, I bought this one from a different seller. This seller is also fulfilled by Amazon. It is working fine till now. I am still in the coverage of 30 days. I hope I do not have to return it. So far so good.
Summary: didn't realize the damn thing was locked but found a ATT store who would unlock for me. the only bad thing was that the seller did not clear her stuff and I had to clear her contacts, photos, and a lot of personal info that could have been used against her if I had been a criminal. be careful what you sell in electronics!