You read as fast as you read. As long as you’re enjoying the book it’s a total win.

I’ve written my share of screenplays that I’ve turned into little indie movies. The trick is after that first draft going back and placing hints at the ending act earlier in the story. Someone shoots someone else with a hunting rifle at the end? Go back and make that character’s father an avid game hunter with a throwaway line or two in act 1. Stuff like that. IMO nothing good ever goes out before draft 3. First draft’s for groundwork, second draft’s for smoothing and clarity, third draft’s for details. (The after that it’s all about technicals like grammar, etc.)

At the time of its release, Jurassic Park got pretty huge. I still love reading it every couple of years.