It's the best riser-sim turned into giant robot anime ever. Also, most likely the only. Anyways, considering how they just took the story out of nowhere and only used the characters from the iDOLM@STER to make an anime, it was pretty good.
Yeah, I enjoyed it. Some of the plot twists were really stupid but the ending was good enough to make up all the stupid stuff done on the way there. And iirc there was relatively few filler episodes, which can't be a bad thing.