Warning for diesel owners - I'll never have another

To be fair, the DPF should have been explained to you when you bought the car. I know a few who've fallen foul of that little problem. Try it on a new BMW X5. It makes £800 look like pocket money.

As regards the rest, maybe the issue is with Vauxhall? I've put the best end of 300k miles on a Nissan and Honda Diesel engine over the last 5 years without any issue whatsoever.