Re: Star Fleet Battles Starships
In SFB, the ships are, indeed, traveling at low (for Trek) FTL speeds in combat; the max combat speed is a tad over Warp 3 (31c, to be precise, although the fastest seeking weapons travel at 32c). Energy considerations typically force speeds to be a bit lower, as does turn radii for many of the ships.
I wouldn't necessarily try to simulate the mechanics of SFB in Hero, though, despite their similarities in using segmented actions. If you are trying to do Prime Directive Hero, use Hero for PC-level actions and SFB (or the simpler Federation Commander)