Soldato
I don't know about the OP, but spunking 15k on a car that is slower than my last car would be a no go.
Let's just say that you have rather "unusual" buying needs.
It would have to be the 330 or 335 IMO.
I've outlined why i recommended a 325i in coupe form above. And i've also mentioned that if he wants a saloon and doesn't mind about it being Pre-LCI, to get the N52 (254bhp) 330i. Will be quick, more reliable than the N53 engined ones and still be plenty quick enough.
I believe the 335s have just creeped in to his budget, too (albeit in SE trim).
If he doesn't need 306bhp+ i would absolutely not recommend a 335i over a 330i. The 335i's have plenty that go wrong with them, and even if you have a warranty, you could still find yourself at signifcant inconvenience when (not if) it breaks down repeatedly.
TBH, from the OP, i got the feeling that he wants a car with a bit of punch, nothing too crazy, but something that isn't chavtastic and looks more professional and respectable. A pre-LCI 330i M-Sport would do the job IMO.