The protein is OK. It does have a lot of sugar in it and a lot of people have some alergy or sensativity to milk.
The fat in milk is not particularily healthy.
Cow milk (whole)
Nutritional value per 100 g (3.5 oz)
Energy 60 kcal 250 kJ
Carbohydrates 5.2 g
- Sugars 5.2 g
- Lactose 5.2 g
Fat 3.25 g
- saturated 1.9 g
- monounsaturated 0.8 g
- polyunsaturated 0.2 g
Protein 3.2 g
To me this seems like a lot of sugar to get relatively little protein.
Low fat milk is an option for those concerned with fat intake but low fat milk is reconstituted from powdered milk and poteins may have been damaged in the transition.
Given the low levels of protein in milk, it's cheaper to get your protein from whey and you avoid the extra sugar.