I'm just off the phone with batterystuff associates, Josh, and later Anthony were extremely rude, unprofessional, and impatient, could not answer any general questions, and were also not transparent about their company's policies. That is not the experience one would expect when dealing with a "reputable" company. In full honesty, I get much better responses when buying off eBay.
I happened to be in contact with RV Upgrades and Aircraft Spruce associates, and their customer service is actually of high quality. This is just my experience and the data point for others who were trying to purchase battery-related products.