The damage and chance to stun are incredibly low, especiially without Second Shot, and I literally only use it to shoot Gel Zon's jetpack and tag bees. It's only there because I like bows and electric attacks.To be fair the shock bow is one of the best weapons for a melee build due to its built in stun chance and likely the best for melee tech for Merc its likely a vampire weapon.
I did find out that the Hirudo is a fantastic weapon for Smugglers, at least if they're specced for ranged weapons. It probably works well enough if they're not.