If your car has some mileage and the leather is starting to look worn THIS IS A MUST. Get the Rejuventor and Pristine Clean. Big difference. But really you should use it twice a year for basic maintenance of the leather. I do it on all my cars. Really maintains the leather to look close to new.
If your leather is just shot do the leather dye restoration. Unbelievable results. Follow the instructions and take your time.
I actually just ordered more RO/RC on Monday. Awesome stuff!