sentiment in here says monero is the best privacy coin and i would agree. the team adds more and more security and privacy features to the coin as time goes on, and they're even working on a private browser called kovri, kinda like tor

i've also come across deeponion (by accident, actually) and it looks like it has a solid team as well. what convinced me to get some was their q&a by themonkii, watched a couple and just felt like it was legit.