This. Seriously, their algorithms and mathematics are public and under constant scrutiny from the entire crytographic community. The vulnerabilities in RSA are

This. Seriously, their algorithms and mathematics are public and under constant scrutiny from the entire crytographic community. The vulnerabilities in RSA are known, sha already has a third version ready if a systemic weakness in 128->512 bit sha1/2 is revealed, and AES may require 512 bit keys for guaranteed security in the future, but seems solid. They can't backdoor a math function because all 3 have been implemented by dozens of libraries and programs independently.