Jess and I don't have a texting plan for our phones. Therefore, we are particularly annoyed with spam text messages because they cost us $.20 each in order to be annoyed. We don't get them very often, but Jess just got one and I decided I wanted to stop them. To be clear, these aren't just wrong-number texts, these are unsolicited-advertisement texts ("News alerts for your area! Text 'Yes' now to sign up!"). We're OK with humans texting us occasionally but I don't want to be paying to get ads sent to me.
So, I called T-Mobile's customer service. I had to work my way through a voice-prompt menu but it was fairly short and at the end I was actually connected to a person and not put on hold. I told the CSR my problem and he offered two options: turn off texting completely or block 3rd-party texts. 3rd-party texts are advertising services, bulk-messaging services, etc., basically the kind of things you never want to get texts from anyway. So I said that a 3rd-party block sounded great. He said sure, activated a 3rd-party block for both of us and asked if there was anything else he could do. I asked another unrelated question about my account and when I hung up I checked the call time: 5:18. Subtracting out the time spent on the unrelated issue it took less than 5 minutes of my time to get the issue resolved.
No charge, he never tried to sell me something ("While the computer's pulling up your account information let me tell you about our new...." -- that annoys me), and he was polite and competent.
Compare this customer service experience with the previous one from AT&T. That difference is why I will be very sad if the T-Mobile buyout by AT&T goes through.