HP 12C - refresh batteries or not?

[jthole]

That was a good decision; one of the batteries already had two pinpoints of corrosion. Since I bought a cheap ($15) Malaysian 12C for daily use, I have just removed the batteries of the older one, instead of installing fresh ones.

The Malaysian unit (1996) has a surprisingly good keyboard, even if it has painted keys. No rattle, and all keys have a positive 'click'.