on the over boost you get 500Nm for a while .. how long I don't know
also on the 35is you get hill start assist .. according to the sales blurb (plus 10db louder sports exhaust)
adaptive suspension and DCT as standard etc ... also but may be wrong on this you get the N54 engine twin turbo not the N55 single turbo on the newer models.
Plus oil cooler on the driver side lower air intake