Arcane Power/Empowering Echo vs Wizard Spirit/Double Casting

what do you think to keep empowering echo lv.1 - magic skill
for 20 minutes, increases the user's magic mp consumption by 35% and m. atk. by 25%. & maximizes magic efficiency by increasing m. atk. by 30% and mp consumption by 10%. every second, 50 hp is consumed. & arcane power lv.1 - toogle skill
maximizes magic efficiency by increasing m. atk. by 30% and mp consumption by 10%. every second, 50 hp is consumed. and not learn
double casting
lv.1 – buff skill
all four elemental stances are activated simultaneously, and you can cast multiple elemental spells at once for 30 seconds. also, decreases mp consumption by 50% and magic skill reuse time by 5%. &
wizard spirit
lv.1 – buff skill
increases m. atk.+20% , m. critical rate +50%, p. def. and m. def. +20%, and magic evasion increased by 2 while reducing mp cost for magic skills by 50% for 30 seconds. when you receive magical damage, the damage may reflect back on the enemy.

http://www.youtube.com/watch?v=90nerlodn24
/discuss

 

no.
/10char

 

long answer:
empowering echo no because it doesn't stack with wizard harmony (if i'm not wrong, it could be another buff or sonata).
arcane power no simply because wizard spirit is generally better.