There is often a weak point in these mixing systems, and that is that somewhere in the world there must be a computer/s doing the mixing, and how can we trust that computer is not being monitored somehow.
tell me which would you trust to use if let say both of these are 99% anon:
1) 99% of all Anon coins out there that is using mix-node
or
2) Crypt hard-to-trace p2p wallet to wallet with no mix node involve.