I prefer a more old-fashioned respect system myself. Simply read a user's post, then decide from the content if it's worth anything. I know that it's more modern to have other people judge things for you, but I'm weird like that.
Honestly, I don't think it makes much of a difference. We threw out the old karma system and that worked fine. Then we migrated over here and installed the original one, and I might have used it once or twice for something particularly insightful.
Ahaha no, let's be serious here. I used it when people made especially clever puns.
I've been a member for quite a while now, so most of the opinions I've formed of people have been formed based on discussions I've read rather than on initial impressions from the old karma system. That makes me supremely unqualified to judge the old system--or indeed any of them--since by the time the system produced any measurable results, I'd already come to a conclusion independently.
I will concede that this is an improvement over the old system in that users can now get a more accurate sense of what sort of behavior is praiseworthy. I'm just kind of apathetic toward the whole thing, I guess.