Very often foreign students who come to study in other places have necessary to share flat.
I never share habitation with somebody then I can only assume what can be positives and negatives.
Advantages is that for student flat-sharing is very good experience to live without parents.
He have to buy foodstuffs, to cook, to do homework and to pay the bills alone.
If share flat with anybody, will be person with whom can talk and discuss on various topics.
However there are and negatives by flat-sharing with anybody.
Your flatmate can be very noisy or too bored, he can be untidy or be obsessive about cleanness.
Also is very irritating when your flatmate has bad habits to take your food from icebox.
I think there is nothing wrong in flat-sharing, anyway it will give great benefit.