When I bought my 780 the leather was in rough shape. The back seat was severally cracked and pulled away from the one of the headrest. I tried a number of products; furniture leather restorer, ArmorAll Leather Care and others that didn’t really do anything. I got a hold of a local Italian leather craftsmen (because central NY is swimming with them) and he said that the best stuff for price and effectiveness is Clarks Leather Lotion.
I’ve been using it ever since and it has saved my seats. It has no dye and it rehydrated the leather like a dream. The cracks are gone and the scratches faded. I reapply it every two-four weeks. However, it the beginning I coated it on every three days for a week or two.
Im sure there are other products but I’ve had great results with this.