For the price (growing up - and yes, I bought them as and as "the disc scratched"), the cars have a quality / lower price. Indeed, cars are handled by small that can easily knock them down, quickly altering the electronic circuit. This may be due to manufacturing, ancient, some models of which the switch is below (I speak of the models presented here). New products (tractor / backhoe and other TutTut'Animo) the switch is present on the sides, do not look as fragile. I did not redeem those.
