I've seen both the Chinese Version first and this one. Highly emotional with an incredible twist at the end. I'd say the friendship is better developed here, while each individual character comes out better in the Chinese version. Its also important to realize that the way the Korean version ends is quite different to how the Chinese version does, just as emotionally Jarring but I have to say I think the Korean ending is much deeper on the meaning of friendship at the very end.
Watch both, it's worth it. I would keep the order Chinese first, Korean second.