formula brands

Au

Does anyone know if it's okay to switch in between formula brands? how did you choose the right one for your baby? my baby girl is one week old today and we're combination feeding... breast and bottle, via advice from our pediatrician. so we've been using the samples of formula we'd recieved while i was pregnant, once we get through those, I'd like to decide on one specific kind, but is it okay to switch them up?