Flickering or pulstating Headlights

Here's what I have in mind, I'm done with all the rebranded Johnson Controls junk but I don't have the money to step up to an AGM battery (Optima):

Duracell Ultra Gold Battery for 1970 Plymouth Duster V8 5.2L 375CCA Optional Car and Truck - SLI24M at Batteries Plus Bulbs