I had ETS fmic and piping in my N54 335i. It was a very noticeable and my 2nd. favorite improvement after remap. The car took double the time to heat soak in the city heat vs stock, which was huge!
Retired: 2005 N52 E90 330i Sport 6AT
Retired: 2007 N54 E92 335i Sport 6AT
Current: 2012 M57 E70 X5 xDrive35D