There are no spoilers in this review.
Avengers: Infinity War is, in my opinion, an incomplete story for the Avengers. Without spoiling anything, the movies leaves them all confused not knowing what to do, or where to go. But for me, it is not an Avengers story, it is the story of Thanos. I think he has equal (or maybe even more) screentime as any hero. The movie explains the character fully, tells us what he is, what he wants, and takes us on a ride through his emotions and his journey to complete a dream. And it ends with his story ending. I honestly think that this movie is about Thanos, and he gets better treatment than any villain has in any MCU movie at least. I can actually understand his point of view, and even though I despise him, I also empathised with him in for a bit. The movie ends with his journey complete, and since I see him as the main character, I am fully satisfied. Yes, I will watch Avengers 4 and be crazily excited for it, but I will always view Avengers 3 as a complete movie.
Now coming to the heroes, the movie services most of them very well. I think the Guardians aren't shown as well as they could have, and Wakanda isn't as big in the movie as shown in the trailers. The big winners coming out are Thor and Dr. Strange, who should see an increase in fandom after this. Cap, Iron Man, and even Hulk were held back somewhat I think. They were given some outstanding material, but they aren't the main focus, even among heroes. Performance wise everyone does really well, especially Benedict Cumberbatch impressed me and Robert Downey Jr. was outstanding as usual. The characters all see their arc forwarded in some way, and it should neatly continue in future movies.
Action was spectacular. That's all I can say. Seeing these heroes, who all have diverse powers, working together is interesting combinations was a ton of fun. Especially since in the other Avengers movies the characters have the same punch-y sort of powers.
The movie itself looks beautiful. It has the kind of scenery that has not been seen in other Marvel movies, they truly made the world seem so enormous that I want many more movies taking place outside of Earth. One scene in particular, containing a surprise cameo, is breathtaking. I want more of this please please please!!!
There are cons here though. There are some scenes that weren't really necessary, and in a movie like this, you need to utilise every second you have. Some detours were not appreciated, especially containing Thor. Those seemed like a filler in a movie that does not really need it. Also, if you want to see all the Avengers all on screen together, that's not happening, so set your expectations before going in.
Overall, I would say go watch this movie as soon as you can, before some idiot spoils it for you. Also, seeing a movie like this with a full crowd is unlike anything else. Go experience it!