The best thing about TERA is the high level combat. Unless you're fighting BAMs and have experienced mid game dungeon boss battles then you don't know how good TERA's combat is. It features the most visceral and engaging combat out of any MMO. Its truely nextgen, unlike Guild War 2's combat which is just another tab targeting SWTOR spin off.
The problem with TERA is that aside from the combat, everything else SUCKS. The questing system is old EQ style garbage leaving the combat as the game only redeeming quality.
While the game over all isn't that good, I'm glad that I played TERA because now I know what a nextgen MMO combat system should be like. Tab targeting is dead, you hear me Guild Wars 2? Seriously TERA combat totally wrecked Guild Wars 2 for me, I'm tired of being a god damn turret in every MMO.