There are meters out there (I have one) that use mercury batteries which are no longer available. The Wein zinc-air battery is a replacement, but according to the guys at the photo store, it only lasts about 3 months. And the alkaline replacements may or may not work well, because they are lower voltage than the mercury batteries. So I decided to upgrade the meter rather than buy batteries 4x a year.
Originally Posted by summicron1
So I switched to meters that uses easy to find batteries, and also had a flash meter capability.
Gossen Luna-Pro F - 9v rectangular battery (aka transistor radio battery for us old folks)
I also like the dial/needle combination, as it is easier to use than a digital meter. I can instantly see all the different f-stop+shutter speed combinations.
Minolta Autometer IV - AA battery