For me that easily the best Michael album since...Thriller, yes the demo could have been a little more polished, but I really like the sound "behind the scenes" of these demo, that really feel like the early 80's vibe; I think the estate/Sony (and I hate their past album, except maybe Bad25th) have done a good compilation job, it's hard to choose the good songs to put in this kind of project, but that work here imho, all these demo are a good mix when you listen the full album.
For the division of fans, I think sadly that a long story with Jackson fans because of his career choices, for example I'm fan of his pre-bad period, specially the late 70's mid 80's period (including Captain Eo); I remember of a very good site and forum because of this division "mjearly 80's", we can agree or disagree with that, but that a long time problems, and I think for lot of fans, these pre-bad demo are logically not their cup of tea; okay behind the mask demo is rough (very good for me but maybe a little too "demo"), but to say the remix of 2010 (who was imo an abomination) is better, I can't understand that, except to have extremely different tastes.
For this project, I really how joyful, simple and beautiful these songs are, there are something very powerful about these songs, 40 years I still can't understand how Thriller the album/demo are so amazing, very something magic about the core of the sound, very hopeful, that the same thing for Chicago1945 and Dream Away.
Sorry if I'm a little judgemental, but that my point of view of peoples could have different opinions for the same subject (Michael Jackson), and thanks you Sony for celebrate Thriller with new songs.