/u/commiespaceinvader did an excellent run-down on nazi experimentation in this answer of theirs. Mengele's experiments did not advance human science one iota. They were flawed premises carried out haphazardly by a second-rate medical doctor. The only true thing of value society gains in 2017 from the SS medical experiments is a warning about how the promise of unbounded research and not being held back by moral scruples can hold a great attraction to some professionals. Additionally, this type of research environment encourages not only sadism, but also methodological sloppiness to produce immediate results justifying such extreme measures.

But for the most part, the SS medical experiments were junk and of little use to subsequent researchers.