I have used Lucas supplements. Not on my new TV thought. Lucas is good stuff... Top Notch. They are very active in Motorsports, which is a sign of a good company. Teams will not pump garbage threw a $100,000.00 engine.
The only thing I dont like about there oil additive is it tends to adhere to parts better then oil. Or it helps oil adhere to parts. That is good and bad. In racing applications you ussually dont want that, Infact a windige tray or dry sump system is used to do the opposite ( that is my mind set )
I know alot of guys use it in the semi's, and Farm equipment.
If you are lookin for some miracle fluid to keep your engine new forever, nothing beats regular oil changes. More often then MFG reccomend. Keep in mind. Most new cars are throw away, and everyone wants low maintenence, or no maint. Extreme conditions warrant more frequent fluid changes also.