The most effective curation comes from the middle of the road people that are surging, not from the big fish, I've found. With the big ones, your vote gets pushed down and you end up with .001 SP usually. They get 100's of votes and unless you have the SP to swim in that tank, you might be better served to vote for the person that gets a 100 or less, but get's those few valuable votes to make the post moderately successful. Statistically it's true I've discovered.