Never used them yet, and probably never will unless England goes Artic! 
Lizzie , on an empty road, please check your brake distances :-/
The thing is Cem we rarely get snow / ice lasting on the main roads for longer than a few days, if that. So I adopt the system I have used whilst driving a million miles on business.
Always drive to allow for the road conditions and the condition of my car.
Use headlights when visability is reduced.
In snow and ice take great care keeping speed down to what the road conditions allow.
Leave plenty of distance between you and the vehicle in front, behind, and at the side, especially when passing lorries on the motorway, with the continual monitoring of the overall traffic situation as far ahead, and behind, as possible.
Maintain the road tyres to the correct pressures, ensuring the tread is at least 3mm, if not replace tyres before winter with a leading quality brand.
If necessary use your skid pan training, including the driver training given to me by a police 'A' driver, and experience to the full.
Keep fully alert for all eventualities, especially if driving at speed, allowing for other peoples errors.
These are obviously my rules, but as I said Cem, they have done me well when professionally driving, often at high speed.
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Topic: Are winter tires worth the purchase ? (Read 2224 times)