I went out to my truck and grabbed my 25 yr old maglite. I'm not sure when I last changed the batteries and not sure when I last used it. It's not even strapped down, it rides between the seat and the fire extinguisher.
Turned it on and it works.
Most of the flashlights around the house are Harbor Freight or HF knock-offs (is that even possible?).
My Blue Top Optima is 8+ years old, bought it used 6 years ago. It lives in my trailer where it's fully charged before a trip. It powers the fridge, camp lighting and usb chargers. Recharged by 200w solar during the day. Sometimes I charge it before storing the trailer. Still kicking.
That said, Mag was making a completely different product at that point. Units produced much later than that have been made of thinner aluminum, crappier alloys, and have piss-poor switches; as well as unreliable... Well, whatever they call that insert that retains the bulb holder and batteries.
I can't quite remember when Optima became a lottery, but they changed as well. Mechanical failures of the internal rails give them nearly a fifty percent failure rate at this point.
You just gave me an idea, though. Maybe I'll buy a NOS vintage unit and convert it to run rechargeable lithium cells. If it works long enough, I can put the Malkoff stuff in there. I really want something that will snap into what I've got, as it's a very convenient spot.