I had the opposite problem. The soy gave me issues. I do like the myoplex brand though. In either soy premixed or the powder is good. Not so fond of vanilla but the choc is good. The strawberry is ok. Hope that helps!!
Coke was my thing too. I drink Minute Maid Light Lemonade. It is 5 calories and 2g total carbs but 0 sugars. (I don't get how that is but that's what the label says!!) I just can't get the protein drink or water out so early.