Which one should I be drinking: soy milk, rice milk or cow's milk?

Just to add to the confusion, there is also almond milk!

However, seeing as I actually have all three of these different types of milk in my refrigerator or pantry, I thought I would do my own investigation. Using a standard serving size of 1 cup (8 fl. oz.), with all three being fortified/enriched with vitamins and calcium, as well as organic): unsweetened/plain soymilk, non-flavored rice milk and fat free organic cow's milk, here is my experience:

My scale:
("++" = excellent; "+" = good; "-" = ok; "--" = poor)

Soymilk
++ protein (7 grams)
++ cholesterol (0 grams)
++ carbs (4 grams)
+ shelf life
++ 100% vegan
+ calories (80 calories)
Bottom line: Good for protein and cholesterol.

Cow's milk
++ protein (8 grams)
- cholesterol (only 5 grams, but others have zero)
+ carbs (12 grams)
+ shelf life not good, unless buy powdered form
++ whole milk for infants and toddlers; contains fat needed for their developing brains
+ calories (80 calories)
Bottom line: Good for protein. Others are slightly better if watching cholesterol.

Rice milk
-- carbs/sugar (has 23 grams; double of others)
++ cholesterol (0 grams)
++ shelf life (up to one year, no refrigeration)
++ 100% vegan
- calories (120 calories)
Bottom line: avoid if watching carbs/sugar and calories. Good to have on hand in pantry. Good if watching cholesterol

So, if you are not vegan, have no lactose intolerance, then it depends on taste and what you are needing in your diet, whether you are needing more protein (cow's milk and soymilk), or are watching calories/carbs (avoid rice milk).

Though I am not an expert, I know something about this as I have always had a strong aversion to cow's milk and have researched to find out why. Basically, we should NOT be drinking the milk of another animal. Once we are past weaning(mother's milk) we should not have animal milk in our diets at all. Many people have a problem digesting it and it can also actually create calcium deficiencies in later life as the protein in animal products can cause the body to eliminate calcium. Also, it is more fattening. Another thing is that it is mucous forming.
I haven't had any cow milk in my diet for thirty odd years and people remark that I have the skin of a teenager and I am thirty eight.
You are best to get your calcium from green leafy vegetables, like kale and brocolli, etc.

Soy is high in estrogen and in this county the beans are often genetically modified. It is better than cow milk but in moderation. It is high in protein but can also be high in fat.

I have recently read that rice milk is the best as long as it's organic,contains non gentically modified rice and doesn't have added sugars. Rice milk is lower in calories than soy and cow milk. It is also lower in protein but if you are getting lots of protein from healthy fish, beans and lentils, you should be fine. Try Trader Joe's Rice-Um". It is lower in price and has very little fat, but 30% calcium and Vitamin D. Also "Naturally Preferred Rice Milk" has added acidophilus.