Right now in my cars I have Kirkland batteries from Costco, and an Auto Craft battery from AAP. I'm happy with both brands. In the past AAP has been great about replacing my battery during the warranty period. And Kirkland batteries are a very good price for the specs on the batteries.
One thing I've heard mentioned is to get a Walmart battery, because if your battery ever dies on you, chances are there's a Walmart near buy to swap it out at. If that gives you comfort, then that's something to consider. But for me, I'd rather get a Kirkland or AAP battery.