Avast and Bitdefender, especially Bitdefender is not far behind Kaspersky in terms of "robust". I recently watched a @jitechsolutions video where they test Kasperky Endpoint vs Checkpoint Endpoint. All files on the Kaspersky machine are encrypted.
pd:
If it is against Zone Alarm, I choose Kaspersky. If it is against antivirus like Bitdefender or Avast, I think about it.
One last thing, what bothers me about Kaspersky, is that it is the only av that I know of that doesn't work in 64 bits, it only has modules. (The av installs to x86 program files, not program files.) Independent that has modules in 64 bits.