A friend would like to try ESET Smart Security 4 on his system to see if it eliminates the mysterious slow downs that he's getting. The install instructions for ESET say to remove any existing AV products before installing ESET. But he does not have any media to re-install his existing AV product if it turns out that ESET does not perform better. Can I just disable his existing AV product and then install the trial version of ESET? Thanks!