I got a price yesterday from the Audi dealership of invoice +$1000 for a built to order 2013. I haven't tried negotiating yet but that seems high. What do you guys think? I have a price on the 5 series of invoice +$750 with an addition $1000 off voucher for the BMW test drive I'm doing next week. Since I'm comparing the A6 to a rwd 5'er (don't need all wheel drive) the prices are closer but the A6 still has a clear advantage and I'm able to get what I want without of a lot of features I don't really want. Audi option packaging fits better than BMW for me.

There are things I like about both but am leaning towards the A6 at this point. With all of the issues 5 series owners are having with the run flats and bent wheels plus the fact all BMW's come with run flats this is becoming a deal killer for me. They offer wheel and tire insurance for "only" $1500 but I refuse to pay $60k+ for a car then have pay an additional $1500 because the tire/wheel package the cars are outfitted with is inadequate from the factory. That is insane to me.

I went through 1) my Insurance Company's car buying service & 2)TrueCar.com (Note: select all the options you will be wanting to get on your car)

They got me the car for invoice pricing to start. I used that as the starting point for my negotiations.

I almost pull the trigger this weekend on a 535xi, I pull out at the last minute over $500. I also have the BMW drive for USA coming up in Aug. Thats another $1000 off the price of the BMW, I might try again then.
Most of the tires and rim problems are on the sport package, if you stick with the 45 profile runflats, you are much safer.
The biggest differnce I notice between the two is that the A6's engine is much responsive, but the BMW is better on the highway.