This game is like the Yakuza karaoke minigame if it was awesome.

There's honestly not much to say about this game it's just a serviceable rhythm game and not much else going on for it. Though that doesn't make it a bad game it's just that there's literally nothing else to do in this game, you just play a song, see your score and play another song to unlock other remixes. I honestly like it better that way, I'm glad I'm not forced into some boring story that I cannot even read just to play some rhythm minigame.
You should see this game as a spinoff like how Gravure for you! is and not a real sequel to the first game as how it was somewhat advertised to be.
I'd say this game is a pretty good fanservice game for anyone who liked the song and cast of the original and should check it out to try out their favorite songs and listen to the remixed tracks.

I do have an issue with the controls though, I played this game on a Xenia emulator, and I kind of felt this input lag and couldn't tell if it was coming from the emulator, my controller, or just the game.
I also think the game is too picky on what is considered a "perfect" button press it's kinda frustrating at times.

i think i spent more time getting the DLC to work than actually completing the game which is funny. anyahoo this isn't really like a mainstream traditional idolmaster game and instead its a live viewer/rhythm game. the point of the game is to experiment with imas unit and song combinations with more freedom than the main imas game would allow due to the whole sim nature of the main series games. There's a TON of songs to choose from for how early in the series this game came out in which is awesome, and there are even exclusive remixes of the songs that are actually bangers so that's also cool. The protag of this game (for what little story there actually is) is a total goober tho so that's kinda lame. anyahoo id say that this game is good if you want to interact with imas but don't want to deal with the simulation aspects of the game and just want to watch cute girls dancing. play if you like idols