I have just tried with 2oz breastmilk (my son doesn't like milk powder) & 2 soup spoon cereal yesterday. He liked it so much & smiled all the time. This serving seems just full for him. Today, I will add a little more cereal.
Before that, I feed some apple juice first, then pear juice few days ago. I don't know whether he doesn't get used to have other taste, rather than breastmilk. He didn't like apple juice much, but he smiled after each spoon of pear juice.