The PMC Starfire Gold is actually the precursor to Federal's HST. The same inventor (Tom Burczynski) designed both of these rounds. Tom left PMC over a dispute with PMC for not loading the Starfire to the velocities called for in his design. (~100fps below optimum)
Federal's HST does have a technology advantage over PMC's Starfire Gold, in that it does not clog as easily and is much better at weight retention.
I would not feel undergunned if I carried PMC Starfire Golds.
Do not confuse the PMC Starfire Gold series with their more pedestrian Bronze series... These are way different animals.