Hydra Arrow, Blade of darkness or Blood Demon's Blade on main?

Curious of what you guys/girls think is the better gear choice in lategame bonus round. Main: Shadow Gear: M.Reaver, Spectral set, Seelenreiser and Hydra Arrow. Blood Demon's blade with 500~ base dmg instead of Hydra Arrow or Blade of Darkness?

Never came that far, so I really have no idea. My guts would say Blood Demon's blade, but the 1% health seems pretty risky for long bonus round survival.