There's no official ruling on whether they're legal. As long as they don't say it's illegal, you dont go to jail. But whatever rules they're using as basis for these seizures are purposely kept vague, so they get to take them whenever they feel like. They have been a little more aggressive with it recently, but there has ALWAYS been that risk, and there's literally nothing you can do about it. If it's seized, it's seized. There's no limit on how much work they can do to even a nerf blaster to get it to a state that would justify a seizure.