The visual effects are great, so if you are going for them or you're already a Harry Potter fan then definitely go see this movie; I'm sure you'll love it. For me, there were several things that didn't work plot-wise and each spell they cast really only raises more questions, like "Why didn't they do this sooner?" or "Why don't they do this all the time?". I didn't really like any of the characters except one. He was fantastic and definitely put the movie up to a 3 for me.
Doctor Strange - 4/5
It was visually impressive, lots to like about the story, acting, etc. A few ways they break the Show Don't Tell rule are mostly what keep it from being truly great. There is an incredibly inventive fight scene at the end and don't forget to stay for 2 scenes after the credits.