I got my hands on the precious OPI Black Spotted, thanks to a nail polish friend who sent it to me from France. As you know it was exclusively released as part of the Spiderman collection in Sephora France. I like it better than the crackle effect. I layered one coat over China Glaze Ruby Pumps and you can notice that it's a learning curve. I have seen many girls complaining about it, it's all about the application, which is very tricky, you just need to wait for your base coat to be dry and apply a super duper really thin coat. I have also seen some complaints about Black Spotted peeling off when you apply a top coat over it. I did apply one coat of Seche Vite and didn't have any issues.
Thank you for reading!