A year ago I had 3 new "budget" tyres fitted to my Vauxhall Astra by a local reputable local firm. A couple of weeks ago I had a flat nearside front tyre but did not identify the cause. On removal of the tyre it was more than obvious that the "hidden" wall of the tyre was showing bare metal through the rubber. I needed a new tyre and it was replaced, together with the offside one, which I was told would be "going as well". In view of this and your article, and advice, I shall be taking the car to my garage in 6 months time for an "inside tyre check", that is at the mid-way point of its annual service.