Everyone talks so highly about Kroil/aero-kroil as a penetrant.

i see they have Kreen Magic Motor Tonic also...is that like Marvel Mystery Oil?
any good?
what is it?
anyone use it in their oil? fuel system?

 

I have used Kreen. It is a fuel system cleaner & conditioner. It's not like Marvel Mystery Oil. I've tried a lot of additives over the years and to be honest the only one that I have noticed any improvements from is acetone.