I had great success with the Swissvax leather products
Their leather cleaner and conditioner are great products
and also come in little bottle to cary along in your on the road detail kit.
and for the dashboard/ M leather to restore/retain the matt finish I have used
I am also a great fan of the Zaino leather cleaner/conditioner as it restore the new leather smell
Just have to be careful wiping it off as otherwise it will gloss for a little while