SIMPLE POLL
This is a mere experiment of the general ranked/competitive scene..
Feel free to comment as to why you chose what you did.
Personally, I'd pick the asshole with mechanics. Why? Because I could simply mute him and still utilize the skill(s) he offers. Having a nice guy feed 0/69/0 and cheer on "Don't worry guys! :) We got this. It's only a hiccup." is far more annoying to deal with than someone bm that's at least positively contributing via carry.
Attitude is one thing, but I see it as a bonus. Mechanics are the primary objective (imo).
/go.
EDIT** Mechanics take into account game knowledge, team cooperation, etc.