Ask your pediatrician their advice.
We had to switch our daughter from breast feeding to formula at 3 months. She didn't have a choice, I couldn't nurse (had started chemo). She took to it fine and wasn't picky.
We started with Similac and Enfamil because it's what we had spoken with our pediatrician about. Eventually, we moved to Costco's Kirkland brand. She was never below the 75th percentile on either height or weight.
What our pediatrician could tell us is valid based upon my career in the pharmaceutical industry: he can validate the claims of the larger brands about their products because they've done the scientific research to prove their products do what they're supposed to. Generic brands may have the same ingredients listed, but their proportions are different, and the manufacturing process is different which alters the end product.
We felt comfortable with our decision, but we had to have that conversation first.