my experience with film is very limited.... however I can tell you that as digital shooter focus is NOT one things that gets in my way.... this means that after you make adjustments you should be just fine...
the newer/nicer lenses allow you to interrupt the auto focus servo simply by grabbing the focus ring to make your adjustments...
you might even notice improvements in focusing... my camera has a 51 point 3d tracking servo... i can lock in the eyes of a subject and fire burst all while the subject is moving around....
most of my manual focus is in macro.... for this I looked into a katz eye focus screen and have read many good things about it.... macro is a small percentage of my shooting so I never bought it....
good lucK!
ps - there are quite a few old filmers on the forum here... I'm sure they can answer better.... welcome!
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