Back in the 90's we've had the violent gaming scare and people wanted to ban kids playing these, with the thought that they would turn out violent.
Time and time again, studies have shown no correlation with violent gaming and actual acts of violence. I refuse your notion that because it's a sexual activity i.e. masturbation and attraction, that this time it's going to be different. It's up to you guys to show studies to the contrary. Until then, it's safe to assume that simulated CP is not harmful for adults to consume.
I don't deny one bit that adults who use the products to groom children into thinking it's alright isn't a crime at all. But by it self, with no other context - It's not harmful.