Oil Man,
I've never heard of the product you mentioned. My memory fails me in trying to remember who manufactures Prolong. I've used Prolong for several years, and one particular car, a DOHC 3.0 litre Mitsubishi come to mind. The car had bad valve seals/guides. I put a quart of prolong in and drove the car 25,000 miles with total reliability and a greatly lessened smoke problem.
Good luck, Larry
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