If you're studying guides to set up your home studio or listening room this may seem at first as something that's just not worth spending money on, and you're not completely wrong.
In my opinion it takes a fairly trained ear to understand how a diffusor REALLY makes a difference in the room acoustics. It took me about a month to configure my home studio in a way that this diffusor would actually work.
Now that it does, i'm glad that I got it early. If your budget allows it, get it and give it some time. Don't go expecting miracles though, but trust the math!
Can be easily set on any kind of wall with a strip of double-sided duct tape, wouldn't recomend using the adhesive as it seems that chunks of the base will easily brake off along when you decide to dismount it.
Try not to get too frustrated during assembly, can be infuriating for those who have no previous LEGO experience. Just breath and follow the steps!
Handle with care, don't mount it near doors or passageways! The material is fairly fragile, if you brake it though, that is definitely on you. Don't go asking refunds!