Tempest Car Hire guilty of injustice! *******!

I hired a Toyota Etios sedan from Tempest for a week starting 27 June 2015. Imagine my horror when, on the way back to drop off the car, the clutch gave in and we were stuck on the side of the highway. I barely drove the car for the week, using less fuel than a quarter tank. Apparently the insurance I added to the basic insurance would only cover me if I totally wrecked the car in an accident! however, if a mechanical fault occurs, the client is responsible IF it can be proven that the renter was negligent. How can I possibly have burnt out a clutch on a quarter of a tank with absolutely no riding of the clutch? Any number of the previous drivers contributed to the wear and tear of the clutch. And they take over 3 weeks to inform you it is your liability! What a shocking attempt to get the customer to pay for repairs and maintenance of their vehicles!! Is this why they advertise themselves as the best deal in town? Because they don't pay for wear-and-tear parts to be replaced? I thought a car-rental company's only service was providing a reliable car! Want to be caught in a \STORM?"Go for Tempest !"""