Imo, 8D lead acid batteries are the strongest cranking battery you can get for their cost. There are all kinds of later technology like AGM that may perform a little better but not enough to recover their high cost. 8D's are not deep cycle, they are not meant to be totally depleted, they are meant to be kept charged and then used to crank. I always got a laugh out of customers who had 5 year old batteries that were left at 0 volts all winter and then thought leaving them on charge for a week would fix them. Other side, deep cycles are OK with being depleted and then recharged and will come back to almost original capacity, but even in good condition will not not supply the cranking power a good 8D starting battery will and don't meet most engine manufacturers installation requirements. I couldn't fit 8D's in my boat's small battery area so I went with what I thought was the next best option, 3 GRP 31's. No shore charger to overcharge them and evaporate the water, and twice now at 7 seasons old I pull all 3 and replace them. Both sets at the end of their last winter layup I checked for voltage, all had over 12 volts.
Due to EPA costs there are only a few lead acid battery manufacturers left. For lead acid there really is only Johnson Controls, Exide and East Penn/Deka. So no matter what label that's who made it. Years ago, driving for a chemical supplier, East Penn was a regular customer and nice to work with. Place spotless clean and everyone seemed happy to be working there
