i think meso explosion should be a buff and not a casting Skill same as the nightlord shuriken stars, ho youung butterflys, nightwalker bats or xenon missiles.
meso explosion is a realy low ping dependant skill making almost impossible to combine it with assassinate and get the most DPS to bosses or hunting make in it not viable to player who play with mid ping.
in my case i'm from south america and shadower is my favorite class but i was forced to change my job to dual blade cause i already spend time and effort on my dagger.