UberQuattroAWD

Hi all, I'm a big Audi fan and have had an 1998 A4 2.8 for 6 years. I plan on keeping it since it still runs good, but is worth almost no money with 220K on it. So far, what I know is to avoid the 2002 to 2005 3.0 engines. I also dislike the look of both the A4 and the A6 from those years. As an Uber driver, I'd like something with some room like an A6 or an A8, but reliability is essential for me. Right now my choices are a 2005 A6 3.2 and a 2004 A8 4.2. Which one has fewer problems? I'd really appreciate any advice on this, guys.