Then comes L-16's and finally 2-volt cells. In one way or another all choices involve compromises and it's the consumers responsibility to learn those compromises then make a choice of the least evil shortcoming.
Allow me an example. My car needed a battery. LTH sells 65 amp hour group 34 batteries here for about $90 including tax in Costco. Costco USA sells 80 amp hour batteries for a hundred dollars plus tax. Definitely a heavier weighing battery. The kicker (for me) is an 18 month free guarantee in Mexico and a 48 month free guarantee in the USA.
The only 6 cell battery I'm aware of in an automotive group size that has golf car type cell construction is a Rolls and Surrete. Folks who wish to refer to accurate information regarding wet batteries should download the free Rolls maintenance manual off the web. But keep in mind it is for golf car and heavier recyclable batteries.
When properly cared for good quality batteries give phenomenal life.
And remember when it's too hot to park in the sun, roof top solar panels are useless.