I got a demo Astra hatchback last 2001 April at 9K mileage EUR14950 with alloys. Crossons gave me 12 months warranty.
Luckily, I had it serviced a month earlier 2002 March before my warranty expires. They found problem in water pump which I remember it would cost me EUR550 labor and parts then. But I was quick to tell them it's still under warranty and they replaced it (including timing belt) at no cost.
I think that's a valuable lesson for me to do when buying second hand car. Service the car (in the same garage where you bought them) before the warranty expires.
Btw, our Astra is on 60K now. Never had problem. Fully serviced every 10K. Just changed timing belt. Although I have to admit, 1.4 is really underpower. Otherwise, we love it and it never let us down.