So I've been reading up on all the extensive posts on the Koni Yellows w/stock spring set-up as an option to the DRC. I assume those using it are installing the Koni 82-2516 and 2526 Sport shocks. There is also a Koni FSD option #2100-4044. So I called Koni Tech center in Ky and discussed these scenarios. Koni commented that neither of these options are "approved" for the RS6. They are approved for the 98-04 A6 Quattro with sport suspensions but not verified/validated to fit the RS6. I don't know the intimate details on the differences say between the 4.2 and 2.7t w/sport suspension and our RS6. Also the lifetime warranty would not apply if installed on the RS6. With that said I see others are using it and making it work. I'm facing a decision on what to do, as my DRC is failing. I want to maintain the ride height and feel of the DRC. I know there is also the less expensive Bilstein PSS (B14) coil option vs. the PSS9 (B16). Did also speak with 2 Bennett - they use the Koni Sports and add new springs, all new bushings, etc (fully set- to your liking) ready to direct install - this is about $2200. Just thought I'd throw out what I learned.