Since star ratings seem to be a topic of discussion today, here are some facts about the performance of the star rating system over the years. I lifted this from another site so I don't have all the details about which service was used, how long, etc.
Odds of a player being named All-American during his career based on star rating:
5–Star: 1 in 4.
Top 100: 1 in 6.
4–Star: 1 in 16.
3–Star: 1 in 56.
2–Star: 1 in 127.
All FBS Signees: 1 in 45.
NFL 1st round draft pick percentages based on star ratings:
5 stars make up 1.3% of all players rated, but they make up 17.0% of 1st round picks.
4 stars are 11.4% of all players rated, but they make up 42.8% of 1st rounders.
3 stars are 30.7% of all players rated, but they make up only 7.8% of 1st rounders.
2 stars are 56.6% of all players rated, but they make up only 15.7% of 1st rounders.
Everyone loves to pick out the exceptions to the rule as some sort of rebuttal of the star rating system, but the above numbers show that the star rating system, on the whole, does a pretty good job of predicting success.