Julio Teheran is 5-3, with a 1.83 ERA in 83.2 innings. He's allowed 58 hits. His WHIP is 0.93.
BBREF has him as a 2.7 WAR player so far (2nd among 101 qualifying SP). FanGraphs at 0.9 (48th).
So he's either having a fantastic, Cy-Young-contending season, or he's roughly the #3 starter on a good staff, or #2 on a bad one. Depends on if you use WAR or WAR.