Limited life on Kidde is 5 years as per Guarantee; which is 5 times longer than patch! One at Argos {New cat from yesterday} has benefit of digital display too, at same price as B&Q's without!
Absolutely not a substitute for servicing; but in my experience gas cooker grills regular cause.
Few people have this appliance serviced; even tenants who have landlords appliances checked by Corgi engineer annually {in UK}. Cooker in 95% of cases is not owned by landlord except HMO type dwellings.
HSE research into long term reliability* of CO alarms found Kidde [then also called Nighthawk on some models] & 1 other make, hard to find at retail, were ONLY ones reliable.
*Majority [using cheap co sensor cells] drift off specification after year or so, so don't respond as they are meant to, giving people false sense of security.