Originally Posted by sfax
My main gripe on the statistics and the whole 7C thing is the marketing that makes statements like "big improvements" at any temp below 7C. I wouldn't call a max of 5% on wet and -1% on dry roads a big improvement personally, particularly not when there is a 40% improvement between a new tyre and one worn down to the legal min.
Firstly I did not pay over £2000 for my tyres. As I intend keeping the car and making use of the tyres the only real cost was the wheels which were £600.
You also misquote the "marketing" - the improvements are increased as the temperature drops below 7C - nowhere have I seen this express as a magic number where there is a step change. It is obviously a gradual one.
You are correct that changing tyres well before they reach the legal limit will also make a major change (but again the "40%" is a gradually from new to old not a step change).
Why are tyres so important in Grand Prix racing - because the 1% or 5% improvements counts - the same as the GB Cycling team was improved by 1% steps to make it the winning team. So the 5% improvement is indeed worth having and should not be dismissed just because you don't like the marketing.
Given that winter tyres are now mandatory in most European countries (in one way or another) I think they have proved their worth. If only one live is saved for having them then that makes them good value.