Some APC's are pretty harsh and arn't too friendly on the coating that covers the leather. I've had excellent sucess with Optimum Power Clean diluted 4 to 1. Make sure to rinse your seating surfaces after cleaning them by wiping them down with a very damp towel. This will remove the product and dirt residue off the surface leaving it hydrated and clean looking. Remember shiny leather isn't healthy leather.
While the coating on leather is likely more durable than uncoated leather, I would never use undiluted APC on leather. I often find something like Einszett Leathercare (designed for finished leather) cleans and protects well enough. If you need something deeper consider Leatherique which will deep clean.
Thanks for the replies guys. :xyxthumbs: I used APC (4:1) that day because I had no leather cleaner on hand. I followed it up with Mother's leather conditioner.