ThreatFire compatible with other anti-virus?

I downloaded ThreatFire from ZDNet, but haven’t installed because I have been told more than once to only run one anti-virus program at a time. I was advised more than once that anti-virus scanners conflict with each other and running two (or more) could allow virus infections.
Will there likely be a conflict betweeen ThreatFire and Symantec/Norton anti-virus?
Thanks.