Keep in mind Thorn has poisen that stacks 5 times and ticks 4 or 5 times each. In PVP without the buff that means the poison does 40-50 damage, with the buff that gives potentially infinite ammo that damage is raised to 7 per tick adding up to 112-140 damage not including the damage of Thorn's shots adding a potential 136 on the first 2 shots. Monarque does more poison, but only stacks 2 times, if you're in a rift you'll probably one shot wigh it. In PVP I would prefer Monarque because of it's longer range and AOE poison and 150 HCs sucking on console, but I prefer Thorn in PVE because of it's higher potential dps and ammo economy.