Should I leave bear trap at level 1?

Just wondering if I should leave bear trap at level 1.

no

I see. Is it because 50 mana per cast is negligible at higher level? Because the damage isn't modified by anything as far as I can tell.

Beat trap is the single best thing solo ranger can have in its arsenal. Its damage is quite significant but its most impressive feature is the immobilization--unlike in many other ARPGs where stuns/immobilization skills diminish in effectiveness in higher difficulties, Bear Trap is amazingly effective and powerful all the way. It works on champions, rares and even mini-bosses. It is not immobilizing Act bosses but it deals damage to them nonetheless.

Yeah, that's why I wanted to know whether to level it or not. Wasn't sure if at high level the increase in mana cost is worth the increase in damage. The reason it was in my build was for the immobilize, just wanted to know about the mana cost vs damage from higher level people.