Around 18 hours 39 minutes to beat based off my recordings (10 hours 37 according to post game timer). Most of the time was spent being lost. The final boss took around 50 minutes.
Overall I really enjoyed the game. The main things I would change would be, d-pad control of Samus implemented (analog is flimsy to use), atleast 4 of the EMMI robots couldve been replaced with unique boss fights (very irritating to deal with them frequently when trying to navigate), more unique boss fights overall (alot of recycled bosses), and more memorable soundtrack like the older games. I would probably still give the game an 8 out of 10 if I reviewed it. I was considering hard mode but the EMMI's kill replay for me, so Im not sure yet.