I use neomailbox its very good.
None of the email services are secure enough unless you use PGP. Most of us only buy small quantities so its a bit of a hassle to give your source your PGP key and then get his but for all other correspondence, PGP with any email is a "safer" way to go.
True, If the CEO is visited by the federal government and order to disclose and access an individual's email, they will comply...no email is safe.definitely not hushmail, they've spilled the beans a couple of times over big drug busts... muscle bear being one...