comodo seems to have abandoned the project , ESET selling an AV on linux is shameful, clamAV is quite weak, maybe i will give a try to Avast ; let see.
Comodo Av for linux only works on certain Kernels "older versions" and even at that, i would not classify it as actually working..
Buying a license of Eset for Linux, ia a complete lack of regard for what Linux stands for.
ClamAv works just fine for scanning documents and files, although i have read others praise Avast for linux.
Me personally i use Clam AV for scanning of files, and use "Mandatory Access Control" to help thwart those with the know how to exploit linux, of course depending on the one you use either SElinux or Apparmor, and the time you put into learning it, so that you may modify them further, will matter. Creating custom rules with IPtables or UFW "firewall" will help as well.. If you really want to go crazy and lock down your machine, you can even customize the kernel..
All of this is really not necessary unless you are hunting down hackers and making them mad on purpose