I looked at the A6 before considering the GS F. I forget the three 'levels' it comes in but I looked at the top one. I like the acceleration and the handling but I wasn't overly impressed. The model had all the bells and whistles like the touch pad, enhanced audio, etc. I liked it, not loved it, but liked it.
What I didn't like was the a la cart pricing. The baseline price had none of the bells in my test drive model. After adding every single feature that I saw and wanted, the price was slightly over my upper limit. That was going to be the car I got in a couple of months.
That weekend, I was casually looking at the Lexus web sight, never really considering them but I had heard good things from friends and family. The styling of the GS 350 F interested me. I test drove one the next day and bought it the day after.
The handling was better, the acceleration was better, you got a lot of gadgetry in the base line model and the few additional things they had in the one I wanted was still nearly 20K less than the Audi.
Bottom line, value for money award goes to the Lexus. I'll take 'German engineered, Japanese built' over 'German engineered, German built' if it means 20K less any day.