Thus far I am very pleased with this company based on great service and care of delivery - great packaging. As far as the actual 304 AH cells, I am still creating individual 12-V batteries and have not yet put them into service. I am unsure of the aluminum battery terminals and aluminum bus bars and possible heating problems - hotspots. However, the connections do seem to be robust. A related concern is possible corrosion and heating that could occur because of copper cabling to aluminum connections. I am using an antioxidizer grease at the interfaces. That should preempt any hotspot problems going forward. Initial testing will commence in a few days, but it will take perhaps months before I have enough experience with them to draw conclusions. Stay tuned.