I'm fine with acrylic, but surprised how scratched some of my coasters (I ordered a set of 4) were upon arrival. The white stickers that are meant to cover the light source were also haphazardly placed. In some cases the stickers don't even line up on both sides, let alone being centered, which looks a bit bad because the disc is so perfectly circular. (The misalignment ends up being way more noticeable.)
Great looking coaster, with the Different Light options! But because of the Lightings and the batteries the coaster isn't flat. So it's pretty dangerous to put a drink on it.