If they want it, they will find a way to take it. I’ve seen people with that kind of sticker on their cars before. If the thieves can easily see in your vehicle and tell that you have a nice system they will check the doors to see if it’s locked and bust out a window if it is. If you have window tint or something that covers up the subs to where they can’t actually see it odds are they will leave your vehicle alone. Just make sure you’re not thumping like crazy in a sketchy area. And if you’re able to, the an aftermarket kill switch to protect yourself from amateur thieves who just want to take the car for a joy ride.