Hi Nesivos,
The experience should not be different. A resident and non-resident av solution can be happily run alongside each other. So Bitdefender's 60-seconds AV scanner can run fine alongside avast resident av solution. So is combining avast, MBAM and SAS.
VTZilla extension site and download scan can be made to run inside the browser without conflicts with your resident avast AV.
It is two resident solutions that will give the conflicts, like you have two dogs fighting over each other's signature-bones, providing either less security than you aimed for. There can also be other incompatibilities as certain FWs with certain anti-malware are conflicting. Also Panda non-resident solution signatures come flagged by avast (but that is that the signatures are not hidden), etc. But there is always a way to make up a good "brew" of anti-malware solutions combined with particular browser security extensions to get a good layered overall protection without having to go into "overkill",
polonus
