About the safest stuff I`ve ever used is Griot`s Interior Cleaaner..so safe it doesn`t even hurt the dirt For light work I just use the IQD or 1Z CP.
For leather though, yeah..the Leather Doctor system has a few different cleaners *AND* the proper rinse agents (much more important than I`d thought). You name the Leather Issue, Roger has the right product to remedy the situation. [REPEAT caveat about what a PIA it is to order from him, and also REPEAT that it`s worth it IMO]
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