I installed the SLP rear bar on my 04 M6 yesterday. It took 21/2 hours. I used ramps and a hydraulic jack to lower the rear end as recommended about 5". The hardest part is getting the bolts back into the brackets as everyone has mentioned who does the install. I did not slot the brackets, though, gutted it out and did it with the brackets unmodified. I used the softer (less stiff) setting to start. It does make a difference. The effect it has is very similar to what I have felt on other cars where I added or changed a bar size. What you feel is less squat in the tailend and less body roll. This loads up the front end and makes the steering even more precise. Interestingly, what you feel is that once in a turn, the steering feels almost harder/less boosted which is a good thing for me as you feel you have more control. A good addition to the car. I did this work with the help of my wife for the install of the bracket on the drivers side. The bar is very hard to move over sufficiently to allow the poly bushing to be seated in the bracket and align the hole. Pretty fine wife who is more than willing to crawl under a car in the garage and help out. She is tiny 5' and maybe 115 pounds but very strong (works out and keeps in great shape). Think maybe she's a keeper after 38 years of marriage. Yep, 58 years old and not afraid to get help wrench a car.