Hi Janis

The remapp is undetectable according to the company I use and have been assured by their own admission (BMW technicians) too.

The cost would be about £1000 for the remapp, this is however for it to be done in UK. The company I use do fortunately travel to US,Middle East and Asia to upgrade cars so it may be worth your while giving them a call.

http://www.dmsautomotive.com/

Ask for Mike....