Well, I can say that my Merc can still punish anyone with ease and I run Arsenal. When was the last time Parsely was updated? The Merc class has been updated several times through 2017 so it'd be hard to say it was the same as it was two years ago. I would still recommend trying out the different DPS routs for the Merc and find one that you enjoy, but I'd go Arsenal for my PEW PEW ROCKETS N' MISSILES!