These Doctor Who TARDIS decals are made to last 8-10 years on whatever you place them on, so you can be sure that placing this on your very own time travelling machine, you will have to replace them only as often as you replace your windows.
Bear in mind though, that this decal has absolutely no background. The picture shown has the blue representing the vinyl, and the white is the background of whatever you are placing it on, but there are several colors to choose from.