My son (now he's 21 month la) eat S26...he can tolerate and no problem in "ngng"....My daughter can't tolerate S26 and eat Enfamil...much improve in "ngng" but can't gain weight as fast as S26....I think yr choice on formula depends on yr bb's body!!!
Besides, I have ask Wyeth for "fat" in S26...they said it's features of AHA or DHA (something like that)...cos, they're fat solable matter!!!
But, I think S26 has more nutrient than Enfamil...but it also more "hot air"...so all depends on yr BB!!