I use Obenaufs leather care products. Like Jack, I have not yet experienced a bad stain, so I can't really say how well their products will work on a stain.
I have been treating my leather with Obenauf's LP about twice a year since the truck was new. IMHO my seats, console, etc., look and feel better now than they did when they were new.
They do have a wealth of information on their website. Even if you do not want to try any of their products, you should at least spend some time reading the articles there. Really good information on the care and feeding of fine leathers.
http://www.obenaufs.com/index.php?os...62a712354b9da5