Looking for some collective wisdom here.

I have a 2004 X5 4.4 with 34k miles that is coming off its lease and I'm going to buy it (love this car!). My dealer is offering to certify it for $1600 so as to extend the warranty by another 2yrs/50,000 miles. I realize that the certified warranty doesn't cover everything the original warranty covered, like interior and exterior trim, seals, stereo, navigation system, etc, but it covers the major items like engine, transmission, drive train, electrical system.

I'm interested to hear from others with their opinions and experience with BMW's "Extended Warranty". Is it worth the $1600 for peace of mind?