I was with AT&T until Cingular bought them. Since Cingular became my provider, my service and reception has declined.
Less signal strength, more dropped calls, more calls that never appear as calls but wind up as messages. Many times the phone doesn't ring and a message shows up.
This is true not just in remote areas, but in major metropolitian areas in different areas of the country.
I'm switching to Verizon.

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