S26 or dumax Dupro is good??

Went my little boy in 1mth old we give dumax Dupro but he seem vomit out the milk..went I changed to S26 in 2mth old seem Okey but now he going to 5 mth old his skin seem redness...at his neck,face,hands and eyes area... should I changed back to dumax Dupro? Some that say S26 is good but some say S26 is hiter..??