Which year 335 have you got?
When i first started the motor there was a rattle, almost like a thrust bearing wear, he says it is just the baffles.......it disappeared quickly...something to be concerned about? its 2010 model with only 14k miles, so i paid over the odds, it is the M Sport version too so has the tasty alloys and limited addition paint.
The only other thing that got my attention was the sports seats, didnt seem to be any support for the base of the back, is this adjustable?
I am pretty gobsmacked with the toys this thing has, i know thats more to go wrong, but it has 3 years warranty.