I recently migrated from SprintPCS to AT&T Wireless after being a Sprint customer for at least six or seven years. It might even be nine years now; I signed up so long ago I've forgotten when it even was. It's not that I think AT&T has the better network (I'm rather indifferent about that aspect these days), it's that SprintPCS -- in my experience more than any other carrier, but not by much -- is so focused on acquisition of new users that its service to existing ones suffers. If by "suffers" you mean "barely exists," that is.
AT&T Wireless appears to be slightly less byzantine, but only slightly. But I'm getting ahead of myself.
(Midnight, Thursday, 8 April 2004)