Certainly, it is vastly underrated. Both the mother and daughter are beautiful pieces of fuck meat. It is also from the time when 'teen' actually meant the girl was a teen, not as nowadays a female in her 20s pretending to be a teen, but that was from a time before Traci Lords.
The guy got it the right way round - use the daughter as the hors d'oeuvre and the mother as the main course. I do hope he fucked them both in every hole and then finished off in the mouth of the mother.