I want to post my 2c on Duralast batteries. My feeling is that they used to be built just well enough to last through the 3-year warranty period. All three times I got a Duralast battery, by the end of the third year it would either outright die or become noticeably weak, taking like 2-3 seconds to start the engine, instead of under one second when new. Leave trunk/saloon light for an hour or so or the headlights for half hour, and it could have trouble starting the car. Recently, I noticed that the warranty period on the new Duralast batteries is down to two years. I bet AutoZone got fed up with all those returns and exchanges happening in the third year, and so they reduced the warranty period for full refunds.
I have learned by now that when you use Duralast, it is best to go out and replace the battery as soon as the warranty period is over unless you can afford to be surprised some day. However, it's likely that all other store brands are no better. Based on my experience with Duralast batteries, I feel like they're average at best. I indeed think right now of either rolling the dice with AAP battery using online discount codes or perhaps getting a Motorcraft battery.