Based on subjective listening results our dealer reported, a decent (e.g. Cisco) SFP switch is preferred to the FMC, such as the one I posted elsewhere, which used to be sold under $99 in the past (one may simply use a SFP switch as a more expensive FMC without changing everything else to fiber):
Likewise, native optical network in a streamer is much preferred to FMC due to the power supply and other considerations.