Love my 6
I have an '09 650i. I have never had a car that is this much fun to drive.
The dealer already replaced my nagigation system (under warranty).
If you buy CPO, you will get the extended 2 year warranty for free. You will need to pay for maintenance after two years. But you can buy 2 years of maintenance for about $2K. But I would recommend finding an independent mechanic, instead of using the dealer.
My only complaint about the car is the 09 comes with the older entertainment/NAV system based on a slow DVD drive. The 2010 comes with the new system. But the 2010s generally cost $10K more than an 09.
I am worried about the price they are offering the car for. It is so low it suggests some problem.