Reflux issues - Change formula?

Krysta
My eldest child had reflux as an infant with projectile vomiting and we put her on Enfamil AR and it fixed it fairly well. 
Now my newest baby (4.5 mos) has it too and we're on Enfamil AR (just switched to Parents Choice brand of it due to cost) and whereas my eldest got better by 4 mos and with AR, this one just is getting worse. 
Literally she burps all day long no matter how long we burp her throughout and after feeding. She constantly spits up, it's a never ending waterfall. My eldest would vomit and that'd be it but this one just keeps going. She'll spit up around her paci while we're rocking to sleep 2 hours after a feed. 
Almost every time she spits up, she burps. I'm wondering if, while she does have reflux, she has a gas problem. I know she's gassier than her sister was but this is crazy. No constipation, no crying from gas or a hurt tummy, just burps and massive spit ups. 
Should I take her off of Enfamil AR (Walmart brand) and try Gentlease or a sensitive formula with cereal added to it? Or just stick it out? She's recently started solids but still spits those up too.