Mosca, one problem with your viewpoint is that you might be able to show it's legal according a recent decision by the Supreme Court, that doesn't prevent local law enforcement authorities from going after anyone who has questionable items on their computers. A guy can stand there at 5 a.m. shouting about his rights, but that won't stop the lawful execution of a search warrant and seizure of all his computers and computer-related equipment/articles.

So it's better to err on the side of caution and avoid even the appearance of pedophile activity, than to risk action by over-zealous law enforcement personnel who sincerely believe that playing with a nude 3D model of a 10-yr-old girl (or boy) is probable cause for executing a search-and-seizure in an investigation of a person suspected of illegal pedophile activities.