Not sure about spending lots of money on a good battery for a rib.
Batteries love to be used, start the car in the morning, 50 miles up the motorway for the battery to charge, followed by 8 hours in the car park for the battery to balance out is ideal
regular, not too demanding work is what a battery needs.
But on a rib you charge it up in March and expect it to work like crazy until the end of September when you leave it until the following year. It lives in a nasty, salty, bouncy, wet environment and has to cope with poor quality charging and poking lots of amps down long cable runs
I think that expensive batteries really only come into their own when they are used at the extremes of what they are capable of and when you then expect them to last for years, such as in a commercial work boat
Repeatedly cranking big cold diesels works the battery hard and over time a battery will deterrent because, in simple terms, the plates loose mass as a by product of the process.
The Ďlost massí, which is on the whole lead sulphate, accumulates at the bottom of the battery and ultimately either shorts the battery by touching the bottom of the plates or the plates run out of lead, at this point the battery dies
More expensive batteries have more material in their plates and or more space at the bottom of the battery and so last longer
Under-used or idle batteries will slowly loose performance as a result of lead sulphate building up on the surface of their plates and unless you remove this by cycling the battery (charge / part-discharge) this shortens the life of the battery
Additives, battery pills and boost chargers will temporarily lengthen the life of a battery but nothing beats regular use
On one car I owned I had almost 10 years use out of a battery just because it was in daily service (100 mile round trip to work).
But if you are not cranking a big diesel it is probably a waste of money buying anything too expensive
Get the cheapest battery with a guarantee you can find and replace it every year under warranty just donít say you are using it on a boat.