They are mostly known for giving a hechsher to many cheeses. R’ Saffra held of a kula of Rabbeinu Tam, which we usually don’t pasken according to. Someone posted online that they had emailed him about it, and his response said, “he did not hold cheese produced with microbial media to be cheese in the traditional understanding, since microbial coagulant did not exist at the time of the Shulchan Aruch. He said it is a different product, so the gezerah was not applicable to it.”
Someone else wrote that the Conservative movement didn’t even really approve of his hechsher.