Corsa 1.3 CDTi 2012 model - DPF issues - Corsablues

I purchased a 1.3 CDTi Vauxhall Corsa Ecoflex Active in September 2012 and have had nothing but trouble with it. It is currently in the garage following stalling to a stop on the dual carriageway and required to be towed to the dealership garage. it has currently been in for 5weeks now and they are apparently waiting for a new catalytic converter as a result of the DPF hose blowing and tearing. This is it's 5th time in the garage and I would like some advice of why this may have happened to a car which is just turning 1 year old and only completed 8600miles on the clock. I am well aware of the DPF issues and have been driving it as recommened (once a week for 25mins in 4th gear over 3000rpm) following a full service after 4months and the car only completing 3600 miles due to the engine management function stalling the engine. The sales manager very helpfully informed me that I shouldn't have bought a diesel, although this was never mentioned at the point of sale by the salesmans!!! This issue has been ongoing now for the past year and I have lost all confidence in this car, but unfortunately am tied into a HP agreement. Do I have any legal ground to return the car as 5 times in the garage surely means the car is not reliable and fit for purpose?
Would the recommended weekly trips have caused my DPF hose to blow? Also, if this is correct why have Vauxhall build in a feature where the car is alerting you to change gear? Even when I do take the car for these weekly journeys, less that 12hours later and the DPF regeneration warning light is on again. Is there a fault with my car or is everyone having these issues. I would be very grateful for any advice or support in dealing with this issue. Many thanks


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