I cut dairy out of my diet with no improvement, then did Alimentum, then Alimentum Ready to Feed, and finally Neocate. While Neocate improved a lot of things for him it didn't help with the diaper rash. My daughter did Alimentum and that cured all of her issues. Again, she couldn't do breastmilk with no dairy in it, she still would scream in pain at night.
Both of them have now passed milk trials and my daughter passed soy. We have not tested him on soy as he doesn't need soy. My daughter we tested because when we eat out when didn't want to have to worry about handing her food off of our plate. His poop is better with a blended diet and the throwing up is slightly better. We could probably trial without the wipes, but I am not ready to do that one