The choice of when to choose decals and when to choose car magnets can be confusing at times. Use decals when your designs or lettering will be permanent. These can be produced in full color and shape or size and and you can even install them your self. Many times vehicle decals will be less expensive than car magnets. Vehicle decals are also a great look for your rear windows to shout out your allegiance to a sports team or a son or daughters school.