I saw the commercial for this item yesterday and, all I can say is "Wow."
When you watch the commercial (and you MUST), you'll see a variety of "what if" scenarios that are designed to get you to think, "Hmm, I never had a doorbell, so this might be a good thing." It's worth it, just for the Oscar caliber acting.
Scenario #1 - If a doofus shows up selling magazines door to door, he'll never get a dollar out of you, since you'll successfully (and smugly) be able to turn him down with a bitchy "No thanks, not interested."
Scenario #2 - Is that your estranged hoodie-wearing ex-boyfriend trying to bang down the door? Just scream, "GO away!" and press the "piercing" alarm. It's not like he can knock that thing off the wall, kick the door down and kill you.
Scenario #3 - Working with loud power tools? The doorman is actually loud enough to stop you from cutting off your finger so that you can go answer the door.
Scenario #4 - Got pill popping kids? Install one of the magnetic alarms in your medicine cabinet. Little Johnny will be completely incapacitated and too stupid to just close the door to stop the noise.
Order now, fools!