With this turning into the BanG Dream Discussion Topic lately, I went ahead and finally watched the three movies (the two Episode of Roselia ones and Poppin' Dream).
The Roselia ones were fine. Lots of it was just retellings of events from the mobile game. It was still nice seeing it all animated though, and they turned it all into a cohesive narrative. There was lots of new content too. Roselia isn't my favorite band by any means, but they have a good story and a fun dynamic most of the time. These movies were fine.
Poppin' Dream was amazing, though! More Kasumi is never a bad thing, but this was Kasumi at her best! I laughed a lot at stuff like her passport misadventures or her fear of flying. Their performances at the end of the movie were the best ones of the series, too, at least in my opinion. Good stuff from RAS and Morfonica, too.