Worse than the wasted time of trying to get a decent group together - ninja rollers. Nothing sucks more than having a group assembled where you are clearly the character that *should* receive a specific item you're looking for, only to lose that 1hd axe to the hunter's roll of 98. Now that is hours wasted..
Now, I don't have to worry about that until 10-mans.. which is quite some time in the future.