Don't expect me to be objective when discussing Pedro, but Blue is right on when he compares Pedro to Koufax. Pedro is Righty Koufax. Extreme brilliance over a 5 - 7 year period. Pedro's best years his ERA was more than a run better than the #2 starter in his league and was less than half the league average. Look at the all-time seasons for ERA+ on baseball reference. I think Pedro had 2 in the top 10 (so did Maddux and Walter j) and 5 in top 33 (Walter J. had 4).
[edit - actually, in 2000, his ERA was nearly 2 runs better than the #2 starter (Roidger) and his ERA was nearly 1/3 the league average]