По мне так самый самый это pure-ftpd, очень лёгок в настройках, стабилен, один из самых secure, да и неспроста pub ftp тех же SuSE на нём бежит.
Я создаю virtual users на нём за 2 сек. что есть good.
из
http://www.pureftpd.org/:
Security first.
Pure-FTPd is actively supported, and it was always designed with security in mind, and the code is always re-audited as new kind of vulnerabilities are discussed.
Unlike other popular FTP servers, the number of root exploits found since the very first released version is zero.
The server can run with privilege separation for paranoid security. It can even run 100% non-root, with its built-in chroot() emulation and virtual accounts.
Transmission of cleartext passwords and commands can be avoided : Pure-FTPd has optional support for an SSL/TLS encryption layer using the OpenSSL library.