Maryland law requires 10 year sealed lithium battery smoke detectors by 2018, so there is still plenty of time for this type as long as you are vigilant about replacing the 9 volt battery.
If you don’t have alarms in your house, this is a great way to spend a few bucks! If every wooter who needs them bought them now, think of all the precious lives that could and would be saved.
Do note that your local fire authority/building department may dictate the type and locations where they are required by code. For many newer constructed properties, hard-wired, interconnected, and with battery backup is a requirement.
Bought one for a lady at work since she just bought a house. I needed to replace mine since it was circa 1960. Replaced my parents old smoke detector since theirs was circa 1978. The batteries were a little old only had a few months on them.