I'm going to be unpopular here and say I found it disappointing.
Yes, it gets the gritty '70s atmosphere spot on, the actors are very convincing in their respective roles, the psychological battle between them is well done, but the racing sequences - which surely must be the
raison d'être of a racing movie - are pants. They look like they were filmed at 30 mph and they thought they'd make up the difference with jerky camerawork and a loud soundtrack.
Watch the actual races on Youtube - much more exciting.
I'd also say it actually sells Hunt short. For example it shows him grovelling to join McLaren when the truth is much more cool. McLaren suddenly lost their driver and cool as a cucumber Hunt rang Teddy Mayer and said "well, it looks like I'm driving for you this year'. That's how he got the drive. What a legend.
I found the Beeb's
'Lauda versus Hunt' a much better effort.
Still, if you can but aside the awful race sequences then as a movie it is a good effort.