Don't Necro please....
Nope, they don't do "horribly" later on. They have much better damage & skills than their regular Adventurer counterparts, and have many exclusive KoC quests that make level-ups easy early on.
The only disadvantage? Level cap. is at 120.
But then again, if you don't wanna make a commitment to make the char. go up to 200, the lower level cap. may actually be an advantage for you.
:)
I've never had any patience with them. I got to level 25 or so, most of which was easy quests, such that I went from 1-21 in most part of 1 day. But frankly, the thing the lack is what I consider important, the support skills. Having a warrior means fast HP healing, which they can't do. Same for mages. SO you end up high potting. So no, level cap isn't the only disadvantage. Still, the one skills advantage they get is earlier HPMax skill.