here's what I got out of the entire 8 pages:

Please note these are not my findings but are the findings of everyone that have posted on this thread earlier, this is basically a summary I have put together with hopefully all the info needed by using all the contributors that have posted previously to this post:





DRC REPLACEMENT

Be advised:
1) Without knowing your experience level, it is difficult to help determine if it's a DIY... It is a big, messy all-day DIY job to go from DRC to Koni's/oem springs. If you've never done strut-type suspension work on Audi's/VW's, find assistance or outsource. Compressing springs can be very dangerous if not done correctly. Plus, there are procedures like removing the upright pinch-bolt that can be a real bitch even with the right tools, techniques and experience.

Tools required:

complete set of metric wrenches and sockets
torque wrench
spring compressor
hydraulic jack
jack stands (if not using a lift)
pry bar
container to catch stinky DRC juice
beer

Tools desired:

lift
pneumatics (impact gun and wrench)
paint pen to mark/index strut-spring components prior to disassembly for ease of reassembly alignment
experienced helper
Southern Comfort

You can research this site for suspension procedural write-ups, but nothing will be step-wise exact to the RS6:

http://www.audiworld.com/tech/wheel.html

2) There is one perch height for the fronts and two for the rear----most set the rears on the lowest perch height.

3) There is more rotational adjustability in the front than rears.

4) There seems to be a non-linear dependency between the setting and firmness.... ie. Dampening set at the midway point on both fronts and rears is still very firm.----At least IMHO.

5) The factory springs were retained
6) Adjustable ride-height coilovers do have an advantage over this method. But, you can cut additional grooves into the Koni strut body to achieve the same results. If using the factory spring, the critical measurement is from the center of the bottom mounting eye to the bottom spring perch, that is where the 95% of the ride height is determined.
7) The height is within 1/16" on each corner as before the swap
8) This is a big job! Not necessarily difficult, but time consuming.
9) First impressions:
- The ride height is slightly lower than stock without tucking the wheels resulting in a slightly sportier look
- No more unidentified suspension noises (USN's) from the DRC from normal driving conditions
- Corners like a champ (car has H-bars) with good turn-in and very flat
- Install cost me $425 at a local shop.

10) Purchase the OEM strut mounts online.
http://genuineaudiparts.com/parts/20...T%20SUSPENSION

The Koni's product numbers are:

Front: 82-2516sport
Rear: 82-2526sport

As for the DRC Lines:

I completely removed all of the DRC lines (just like metal Brake lines) that go Front Right to Rear Left & Front Left to Rear Right. And un-bolted the to accumulators crossover valves from the front of the spare tire well. A few pounds savings and do you really ever intend to go back? If you have KWV3's I guarantee you won't. Not sure of the exact content of the fluid but seemed like pretty standard Hydraulic fluid, probably about 10w or something.

THE BUSHES AND SWAY ARMS

you could've done the upper arm bushes as well if they're shot or close to, in order to replace them you'll have to unbolt and lower(or twist it cca 30 degrees) the strut/spring assembly

SETTING THE KONI SHOCKS:
1 - I set the shocks to: Front - 1/2 turn from full soft rebound and stock Koni perch height and Rear - 1/4 turn from full soft rebound and low Koni perch height. Car sits level with a really nice consistent gap around all four tires. Love the ride quality so far and I don't hear any suspension noise at all.
2 - The fronts have about 2.5 full turns of rebound dampening adjustability and the rears have about 1.25 turns... I set the fronts at 1 turn from softest, and rears at 0.5 turns from softest. Also, the Koni fronts have only one lower perch groove. However, Easy enough to cut a groove if ride height needs adjustment. The Koni rears have 3 grooves (approx 3/8" apart)... I chose the middle groove which yielded an oem rear ride height.
3 - If I knew then, what I know now, I would've started at full soft on the rebound settings AND placed the rears on the lowest perch height.
4 - Last weekend I decided to "tune" the new Koni's... Not that anything was wrong with the ride or compliance, but just wanted to ever so slightly soften the ride.
5 - If you poke around on Koni's website, you'll find detailed instructions and info... As other's have said, push (compress) the rod all the way in until it bottoms. Then, rotate rotate using the appropriate allen wrench--- I think full soft is counter-clockwise until no more rotation, and full firm is clockwise with no more rotation.
6 - -non-externally adjustable Koni's are adjusted prior to installation by completely compressing the damper and rotating the shaft until you feel it engage. I then back it all of the way off (soften) and then fully tighten (hardest), noting these positions. This gives me the full known range of settings. I have typically then set mine at the mid point, and left them like that for as long as I had the car, with great results - I love Koni's. For the RS6, I would be tempted due to weight and the general nature of the car, to set it at 3/4's hard. Good thing - these settings may be adjusted at a later time if the results are not desired or the shock has softened with use (typical). Bad thing - you have to disassemble the suspension and free the shock to do it.

The initial settings after install were:

Fronts: 1 turn from full soft rebound and stock Koni perch height.
Rears: 1/2 turn from full soft rebound and middle Koni perch height. (There are 3 lower perch heights)

The new settings are:

Fronts: 1/2 turn from full soft rebound and stock Koni perch height.
Rears: 1/4 turn from full soft rebound and low Koni perch height. (There are 3 lower perch heights)

Ride compliance is now perfect for my driving lifestyle!... The rear ride height dropped about 1/4" yeilding a "level chasis." The car now sits perfectly level!... No rake. Most of the rake was removed after swapping the DRC out, but it was still slightly high in the rear... Softening the rebound a bit and moving to the lower perch on the rears was worth the 4 hours!

FAQ’s

Your description of the rear perches is a bit confusing, how about stock height for the lowest, then each one up a 1/4" more raised.... Sorry, it is not only confusing, but hard to articulately describe... I could be wrong, but I think a stock RS6 with the DRC properly set-up, has a slight chasis rake... I prefer the car to sit level with a full belly of fuel---and the lowest rear perch height on the Koni's yeilds that on my car.

What's your reasoning for a bit stiffer in the front, engine weight, nose diving I guess?
The Koni's range of adjustability is different on the front than the rears.... 2 1/4 turns of adjustability on the fronts and only 1 1/8 turns on the rears. Also, to make it even more confusing, I do not think there is a linear dependence (ie. a half turn from full soft rebound might still be quite firm, but a half turn from full firm will likely feel no different than full firm)

How compliant are the small bumps now? I know it's tough to describe, but all the 1" ruts and holes around town kill my back, so I've been thinking full soft just to be safe...
Noticeably better after last weeks "tuning." I don't think you will go wrong at full soft front and rear.
ADDITIONAL INFO:

BTW, keep your receipt for the Koni's----they have lifetime free replacement to the original purchaser


Another note, I never got the chance to stiffen mine up a turn, but since adding the Hotchkis sway bars, maybe no need. So much of the body roll was removed, and suspension really glides through uneven corners. The combination is excellent.