As you approach the middle of the season, most people are trying to improve the ERA and Ratio categories for their teams.
Many people try to add another hopefully average starter to help their team.
Don't do that. An example of a vulture who is a very good pitcher is Kerry Lightenberg before he was the closer in Mark Wohlers absence. He won three games at the start of the season with excellent ERA and ratio. An example of a subpar vulture that may still be available in your league is Wayne Gomes of the Phillies. He is a below average pitcher who has won 4 games with a good ERA and ratio.