If the lad can justify it then why not?
When i was 18 i had a 1.2 16v dynamique which was my 1st car while i was studying, i bought the 182 just before i finished studying when i'd just turned 21, my 1st year was £1050 fully comp with 0NCB in my own name with my mum on the policy.
2nd year insuring it there just before Christmas i'd just turned 22 it dropped to £850 again in my name with mum on the policy with 1YNCB.
I'll prob keep it for another year then change next summer for something else, M3 or the likes.