What a difficult choice to make!
Having used both, I would have to say
Kaspersky,but
F-Secure, even without a firewall, is a superb piece of software and lighter to boot!!
F-secure is lighter than kaspersky for sure since it's a cloud based program.
By this logic Kaspersky uses the cloud too,but they are
not per-se, "cloud based",like Panda or Webroot which almost use the cloud exclusively!