Just got back from seeing it. I loved it. Always been a big fan of Cheadle, and this was probably my favorite flick of his since Talk To Me or Traitor.
Honestly, it would be tough to call this a true "biopic". Its a movie about Miles, but they dont follow the usual tired trope of starting off as a child prodigy, being discovered, becoming famous, crashing, and finding redemption. Thats actually hinted at early on when Ewan's character asks him about "The Miles Davis Story", which he summarizes pretty funny in about 3 lines.
Best flick i've seen this year between this and The Revenant. Race was a huge letdown. Deadpool was dope, but overhyped IMO.