To start: If you liked the first 2 PA movies, you will like this one. It is more of the same, with a few new inventive jump scares. The movie takes an odd turn at the end that a lot of people may not like. The last 10 minutes are very tense.
I think this movie suffered though from over-editing. There are a lot of very obvious missed opportunities that were probably filmed but cut out in the end (it is a very short movie in it's final form). There are a LOT of scenes in the commercial and trailer that are not in the final film. The "Bloody Mary" scene that everyone has seen is completely different in the final film (I suspect it was more teaser footage than meant to be in the movie). The oscillating fan camera could have been used much more effectively.
Best to see in a quiet theater, there are a lot of subtle noises that you can't hear if the teenagers behind you don't stop talking to each other or playing with their cell phones every 30 seconds.