Enfamil AR vs Similac RS Which is better?

Okay my son is now 5mths n 5days. he is currently on Enfamil AR, he has reflux. I thought it would be better by now.! but no luck. I was at Target and came across the Similac RS which comes in a ready to serve container. Does it work better then Enfamil AR? He still spits up with the A.R. When does this all end....? Im on WIC and i doubt they cover Similac...?