[rondeo]

Anecdotal evidence shows Ca batteries (Supercharge, Century) get the car started and running for years, Ag(silver)/Ca batteries ditto.

The smart charge system reduces fuel consumption in accordance with basic laws of physics.

A DVM plugged into the cigar lighter while driving shows the charging voltage increasing under deceleration and reducing under acceleration.

The difference between Ca and Ag/Ca technologies under the smart charge system seems to be an open question. I suspect it's pretty small, and might not be worth the money.

BTW Cobrin why not use a backup supply while changing batteries?