About 1 hour and 50 minutes.
I died on one of the first encounters with those Ghouls.
I got to say after that I didn't die often anymore.
It seemed to me that after my first monster experience it "clicked" for me and I found my flow pretty fast.
I always die early in the game in games like that because I have to get a "feeling" for the general combat and pace.
After that I only died 2 times so far.