I guess it depends on if we're talking about a player phase Quan or an enemy phase one. A +Spd Quan with a +6 speed buff, Fury 3, and a speed seal hits 44 speed, 47 if he has a speed-refined lance, and 49 if that speed-refined lance is Shell Lance.
Quan can definitely hit some high speeds if built for it.
Well, that also depends on preference. Fury is a nice stat-boosting skill, but it reduces a unit's survivability due to the decrease in HP after every battle. Steady Posture is a nice skill, and he'd achieve 48 speed on enemy phase with it if he has a speed-refined lance, 45 if he has his base lance.
With +6 speed from being buffed the only things Quan isn't doubling on Enemy Phase are typically reds and tome users. Reds he doesn't fear, and tomes destroy him anyway, so I feel you've better options for B. Assuming you're running Speed Tactics or Hone Calvary, of course. If you didn't want to run Vantage, because of his movement, you could even make something like Brash Assault work, as he should be preventing any doubles on Player Phase while buffed.
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