I have played Cabal Online a long time ago. A very long time ago. And though it's got nice graphics (it's got a modern feel, though the setting is more old-style fantasy), and cool looking combat, its gameplay wasn't very fun.
I won't be giving a proper review here, as I can't remember too much of it, but Cabal Online had one MAJOR flaw. There's too much grinding. The game relies almost COMPLETELY on grinding. There's a few early quests, and then the rest of the quests seemed to just be grind, grind, grind till the next level (not even any variety in quests), and next skills. This proved to be too boring for me in the end, and I quit. For this, Cabal Online is a very un-recommended game in my opinion.
The other flaw, though not as much of a major one, is that the maps are too small. The maps are tiny, and you have to go to the next through these portal-like things. I'm afraid in the age of seamless maps, this just isn't good enough, and it could feel small very quickly. Even Dekaron/2moons isn't this bad, at least they have bigger maps linked together!
Good points that award this game 3 points instead of a 0 though, are that the combat is cool, and the graphics are pretty nice. The combat especially, is one of the highlights of the game, and kept me on slightly longer, so that I can unlock the next skill, and it took longer for me to get bored of the attack animation.
All in all though, Cabal Online is a repetitive game that can't really be recommended over the hundreds of alternatives of MMORPGs out there.