[exim] Antivirus for Linux and Exim

Hi,

currently we use Kaspersky to scan incoming and outgoing E-Mail with
Exim 4.89.
My boss would like to integrate some other antivirus on the system and
he suggest BitDefender and Sophos.

I searched on the internet page of both companies, but I just found
marketing-shit.
A chat with the support of both company gave me no other information
but the same marketing-shit.

Do someone use these program and can say me:

- which (damn!) program of the whole pool of the companies do we need?
- do these programs run on a Debian 9 server?
- how much do they costs for a single server?
- maybe a contact to someone technical (NO marketing, please!!!!)
support by that companies.

Thank you very very much.
Luca Bertoncello
(lucabert@???)