"Restore" oil additive

[dwest]

I recently purchased an 89 300CE. I'm very happy, for 7k mi, car has been perfect, and beautiful. My only nightmares come after reading horror stories on this site! Maybe I've got a good one.

PO put in a can of "Restore" with each oil/filter change. I have done the same (twice). He said it was done preventitively. Car has 160K and burns no oil, none. (Leaks less than 1/2 quart per 3K change interval) I am considering changing to synthetic oil. Should I quit on the "Restore"? Maybe I should just leave well enough alone and continue on my present regimen.

Any comments?