Proc is added on the horde lv to my understanding, but this weapon is one of the few that has promise as a good normal weapon. Delay is acceptable, and the damage bonus is high enough to offset the delay.
After conversion expect the following:
Gremling Bane Dagger
1hp
6 25 +8 damage bonus + 4 bane gremling
10 25 +8 damage bonus <-- is acceptable as a gremling dagger in my book.