This is one of my favorite time travel movies and for as far as I know the only one which doesn't have any pardoxes in it. I did have to watch it twice though plus some youtube breakdown videos but even on the first watch I enjoyed it. I also remember watching Upstream Color which is the other movie of the same director which was weird but interesting even though I don't remember too much about that.

Primer is a real classic especially for the budget it was shot with. I also easily give it a 8.4/10