I would say the best is LSing MH, 15 Agi off hand, in general. But it all comes down to who you are fighting and how many are hitting you.
If you fight 1v1 vs melee or a hunter, dual Agi or LSing MH/15 Agi off hand is best
If you fight 1v1 vs a caster, dual fiery or lifestealing is the best
If you fight against more than 1 opponent who are melee, dual agi is the best.
If you fight against more than 1 opponent who are casters, lifestealing is the best
If you fight against a melee and a caster, 15 agi OH and LSing MH is the best.