Semi-slick tyres are unsuitable for road use, state the team behind a comparative test published by Swiss magazine Auto Illustrierte. An evaluation between standard, ultra-high performance and semi-slick tyres conducted at the Goodyear proving ground in Mireval, France showed the racing tyres take much longer to stop on wet road surfaces than their more conventional counterparts. Specialists from TÜV Süd supported the Auto Illustrierte testing and evaluated the results as a neutral partner.