Hi LB!
The SA I spoke to at Coach said I should use their leather cleaner, but not theirs,or anyone's moisturizer. I suppose I could use a non-Coach leather cleaner also. He suggested that just as a way to keep the bag clean. (He cleaned the bag for me before I purchased it.) As far as color transfer, he said it could happen on this bag, but "maybe" if I use the leather cleaner right away I "might" be able to get it off. But the bottom line was when he said, "If you do get color transfer on the back, try to not to carry your bag the wrong way and get it on the front as well."
It's just a fun Spring/Summer occasional use bag so I'm not going to baby it or worry about it.