Having a lot of fun with this! I play Panel Attack as well, and while there are some pretty big differences I like this game's unique take on the genre, e.g. being able to scroll the screen while a combo is going off, being able to catch a falling block with a block from the row immediately below it, etc.
One thing I noticed that is a bummer is that the game slows down noticeably in Mirror mode*, which puts competitive Mirror players at a slight advantage. I've also considered casually streaming the game using Mirror, but I find the slower game speed a little off-putting. Really hoping that performance can be improved to the point where the game performs exactly the same, with or without Mirror!
*footnote: subpar Mirror performance is actually a widespread problem in the Playdate community