I think that choices depend on where you live. Although I am unlimited roaming and never have to pay for it on my plan my provider does not have coverage everywhere. Before I switched to what we have now we actually had AT&T (my calls were constantly dropped inside certain areas of Austin which is not a small town). Verizon just plain irritated me (their plan requirements were way too expensive in comparison to other providers). It came down to where the cell towers were placed, who's signals were boosted, etc. for us. Unfortunately, there are still places that get really horrible cell reception no matter who provides it.
Some people like prepaid phones. I found my contract was comparable to most of them. I think you might want to shop around and compare. Sometimes upfront costs end up costing more in the long run.