Tiff and Vicki show what happens when tires blow, whether run flats are really any good and whether you can race on run flats.
Tom reviews the new Mercedes-Benz SLK.
Tiff sees which is faster around a track - a Mini Cooper or a diesel Skoda Fabia.
Vicki drives that British amphibious vehicle, the Gibbs Aquada.
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Ready to Watch Fifth Gear, Season 5, Episode 4?