I really enjoyed this film! Bare in mind whilst you read this that I went to see the film in 4Dx. I recommend this film if like me, you're only a casual fan of BLACKPINK.
The whole movie is basically like a concert, which I personally didn't mind, as the songs sounded a lot better in the cinema especially since the place I went to would spray water and air and shake our seats during the songs. Although it did borrow a lot of clips from The Show and the 2019 Tour, that's why I'd only recommend this to a casual fan.
If you want something more personal and you don't know much about kpop, I recommend Blackpink's documentary on Netflix (its probably cheaper) as the members talk about their personal lives and their experience going from being a normal person to a superstar.
Overall, it was pretty good and a lot of fun, it was nice to be able to go out to the cinema and watch Blackpink on the screen, lol.