That's fine, I don't anyone is expecting an ace. Mike Fiers has lived with that velocity in his career with a high spin fastball, and he's about a ~2 win/180 IP starter. I think we'd all be satisfied with that outcome out of an 8th round pick who signed for slot value. Murray's great results are also coming at an good age for prospect status, given that he's 2 years younger than the average in AA, so there's some hope that he can surpass that 2 WAR ceiling.