Good question Nelson,

Leatherique, IMHO, is the best of the best. It is the leather product of choice for Bentley and Rolls Royce owners. My last car was an S4 as well and Leatherique was all that touched my leather. It comes in two versions, Prestine Clean and Rejuvenator Oil. The Prestine Clean is enough for most instances, however if the leather was really neglected and you need to restore the proper oils and make the leather supple again, then you can resort to the Rejuvenator Oil. My leather was still in fairly good condition and I did both steps, however I think all I really needed was the Prestine Clean.

As far as the process for using Leatherique its slightly different. Here are the steps assuming you use both products, if you only use the Prestine Clean just disregard any step w/ the Rejuvenator Oil.

1. Wipe down the seats w/ a damp cloth
2. Vacuum out the seats and crevices to make sure you are starting w/ a clean surface, meaning no debris.
3. Remove head rests and follow the same steps listed below on them
4. Apply the Rejuvenator Oil (the darker bottle) to the seats by hand
*** Pay close attention and use a liberal amount around the seams and stitching***
5. Once desired area has Rejuvenator Oil applied, heat up the surface to bring the contaminates up to the surface. I suggest letting your vehicle sit in the sun for as long as possible, others use a heat gun or hair dryer to instantly heat up the seats, just be careful you do not get too close to any plastic or other parts of your interior that can melt due to high heat of the tip of the hair dryer or heat gun.
6. Wipe off the heated surface w/ Prestine Clean (lighter bottle) this should be a clean surface w/ no stains. To clarify, apply the Prestine Clean directly over the Rejuvenator Oil, your leather should be a sloppy mess at this point.
*Stubborn stains may need more than 1 application of rejuvenator oil. Stains or contaminants remove the easiest when the surface is warm/hot.
7. Let the Pristine Clean sit until next seat(s) is completed (15-30mins)
8. Wipe off the penetrated Pristine Clean with a Warm Damp Cloth / Microfiber towel
9. Buff dry with a new cloth. Leatherique will not leave an oily residue or glossy shine to the leather. It is a gorgeous matte finish that won't leave you slipping around.
10. Enjoy your revived seats

Let me know if you have any further questions!

Sincerely,

George @ Detailed Image