FScan has the same limitation as a SCIO, if you are not reactive you aren't reacting to the frequency even if the item exists in your body.
If one follows either one of these it becomes necessary to peel the proverbial onion and for that the SCIO is much better suited than the FScan.
Also what I have done is take the results of the SCIO and am using them on the F125 now. For instance been zapping ZRickettsia_51.frq since yesterday. Today I removed the frequencies that do not appear to do anything and created a ZRickettsia_21.frq.
BTW: There seem to be good results with zapper handholds and footpads and no immediate need for an EMEM.