Ninjustu Skill worth level'ing?

[Rekiem]

I'd like to know if its worth skilling up Ninjustu. What do you get when the skill if capped and how strong are the elemental spells?

[Kaita]

if you do melee/jutsu ninja u will skillup ninjutsu fast anyway.

elemental: ni does ~80-90 dmg, ~110 on full MB.

but main reason to skillup is to make kurayami and hojo ni stick, both very strong.