the updated dme software does create a noticable lag. quoted from BMW SIB 11 13 07

All 335i/xi and 535i/xi models built from June 2006 up to September 2007

The updated software causes a small amount of increased "turbocharger lag" under certain circumstances and, while not substantial, the lag may be perceptible to the most sensitive BMW drivers. X6, 135i, 3 Series and 5 Series vehicles from March 2008 production onward are not affected. If said "turbocharger lag" is a customer's complaint, then the vehicle's DME software can be retrofitted to the original waste gate operation.