We bought a car bed for DS1 ('cause DH had always wanted one - there's a theme here) when he was two & I can't see him getting sick of it anytime soon. I'd say he'd like it till he's 8 to 10. I wish he would get sick of it in the next year so I can give it to DS2 and get him one that's higher off the ground that I can put a spring mattress on - the car is really close to the ground & it'd be too hard to make with a heavy spring mattress.