Also, some security mechanisms can make your home less safe by making it difficult to escape in the event of a fire. A fireman once told me he’s seen people die in fires because there were security bars over the windows and they couldn’t get out.
Sounds great until you think about a fire situation. I think we're just going to keep an extra key very close by but that solution only works because we don't have kids; I'm not sure I would go with the double cylinder deadbolt if we did.
(And yes I know it's against the building code but I also know people regularly do double cylinders on their own personal homes. You'd never do it in a rental, AirBnB or commercial building of course.)