I played it for 2 or three months, until I got a new game. (I don't usually spend lot of time with the same game, I play them some time then move to the next one). It was quite fun but I can't say it was a remarkable experience in any way form or shape. It was nice because you could expend an afternoon just with a couple of matches. The negative thing, aside of assholes, was people that was disconected 90% of time.
Draven was my favorite character, since he did everything...with styyyyyyle. And probably he keeps my "favortie" spot also my best results were achieved with him.
However since I unlocked and started to play Kah' Zix I didn't play with any other character but him until I left the game, it was so awesome and fun and every game was unique since you evolved acording to the situation. But kind of useless late game.