The two Rolls 8D in Dear Prudence cost me a total of about $1200, but I happened upon a special opportunity. About the time I was throwing out the two junk batteries the previous owners had been using, one of my friends in the business cleaned out a warehouse. Back behind a bunch of stuff that had been there for several years there were two brand new Rolls batteries. They are shipped "dry", so there was nothing in any of the cells but the lead plates. As the batteries had never been sold or activated, the full factory warranty was still available. We poured in the acid, put them on a charger, and they proved to be as good as new (which they were).
You can buy cheaper batteries, and frankly most people do. In my opinion, the Rolls are a push or better with buying cheaper stuff- especially when considering the cost and hassle of swapping out a standard battery once, twice, or maybe even three times during the usual life of a Rolls.
Biggest difference, as far as I can tell, is that the Rolls have larger and heavier plates. They also wrap each lead plate in a type of a sack that is permeable by acid. As the plates eventually degrade, and slough off remains in the sack. A lot of wet cell batteries fail when plates begin to disintegrate and enough debris builds up on the bottom of the cell to create a short.
