Lev 10 Skill upgrade choiceFollow

I'm playing my first predator and plan to go Ranger. I'm wondering what is a good choice for the Adept II skill upgrade you get at level 10? My first thought was go with more damage but was wondering if the Ensnare or Dirty Trick upgrade was a better choice. Any suggestions?

I chose Holly's Entangling Trap (the snare upgrade). I also plan to be a ranger and I noticed that they don't get any spells or skills that slow down enemy attacks. It seems like the most unique choice as all the other skills will have upgraded versions down the line anyways.
The way it works is interesting as well. I remember reading a description that the attack rate isn't slowed until after the snare spell wares off (I think you get this from examining the effect when it is on the NPC). Also, the snare seems to ware off if the NPC takes a small chunk of melee damage (not sure about ranged or magic).
The problem is that it is hard to tell how long the decreased attack rate lasts because it doesnt start until after the snare's spell icon goes away. It says it is only for a short time but it seems to me that if the effect occurs after the spell wares off, that it might last for a fixed amount of time, despite the difficulty of the mob. Anyone know?