I had the worst of the worst, Sprint quite awhile back. Only because it was the best price I could find and they gave me free phones. It was a good deal and it worked out OK.
So T-Mobile bought Sprint and announced that Sprint customers would eventually become T-Mobile customers. So one day right out of the blue a very nice lady (English speaking even) called me and very politely said she wanted to welcome us to T-Mobile. OK, fine.
Then she offered me such a good price as a Sprint customer coming over I was floored. And she said it wouldn't go up later. I thought she was kidding, I'd never paid so little for cell phone plan. I instantly accepted never thinking my bill would actually go down that much. But it did and it's stayed there for quite awhile now.
So I'm happy. Not going anywhere any time soon.