Non-dairy milks

 Non-dairy milks have become popular for many reasons. They provide a substitute for milk for people who can't cope with the lactose (or sugar) in milk. They are also an options for those who have milk allergies. They have become popular too since the rise of the paleo movement and veganism.
However they also have their drawbacks. They will usually be more expensive, and are usually UHT (long-life). This means they are not as fresh as cow's milk and this in itself gives the milk a different taste. They also lack calcium and some are very low in protein. Below I have pictured a few available and outlined their nutritional qualities.
Overall cow's milk is the cheapest and the healthiest. If you can't tolerate that then soy milk is the closest milk nutritionally to cow's milk.
Calcium
Cow's milk provides valuable calcium for strong bones, particularly for kids, teenagers and post-menopausal women. A non-dairy milk contains no natural calcium. However most have added calcium except for the organic coconut milk and the oat milk seen below. 
Protein
There is very little protein in almond, coconut and rice milk. This means they are not as filling and not as nutritious as cow's, goat's or soy milk.
Sugar
Cow's milk does have natural sugar (3 teaspoons in 250ml) in it but as it is naturally packaged with calcium and protein it is still nutritious and an everyday food. Flavoured milk should be treated with caution as it has much more (added) sugar, like 25-30g per serve or 6-8 teaspoons per glass! Most of the non-dairy milks I looked at had less sugar than cow's milk with the exception of the Vitasoy Rice Milk.
(Remember 1 teaspoon of sugar = 5 grams).
 
per 250ml:
Almond breeze- 200 mg calcium, 1.3 g protein, 0.3 g sugar
So Good Almond-  300 mg calcium, 1.4 g protein, 8.6 g sugar
Organic Coconut-  no calcium, 0.3 g protein, 0.5 g sugar
So Good Almond Coconut- 300 mg calcium, 1.3 g protein, 0.5 g sugar
Vitasoy Soy Milky-    300 mg calcium, 7.5 g protein, 6.3 g sugar
So Good Soy Regular- 400 mg calcium, 8.5 g protein, 5.1 g sugar
Oat Pure Harvest- 6 mg calcium, 4.5 g protein, 9.3 g sugar
Vitasoy Rice Milk- 300 mg calcium, 0.7 g protein, 14.5 g sugar
Living Planet Goats milk- 305 mg calcium, 8.8 g protein, 11.3 g sugar
Cow's milk- 292 mg calcium, 8.2 g protein, 12 g sugar