Merc dps is the worst subclass in the game. Followed closely by Commando dps.
I do not agree on you with this statement that you made. Commando and merc are a mirrored subclass so they are basically the exact same except for names, armor look, different animations. So there is no way a "Merc is worse than a commando" or "Commando is worse than a merc" They are the same attack wise and both have the same escape issues.