I tried a lot of security software on different servers, but ultimately I stuck with BitNinja. It was not so expensive, and it works nice. It has a very easy interface and can be used by beginners, unlike the others you mentioned.

BitNinja is a feature-rich script and application firewall that provides an all-in-one solution for shared hosting servers. The BitNinja API allows easy integration with any third-party software, including WHMCS, cPanel, Plesk, and more.