I did look to see if this was covered elsewhere and it doesn't seem to be, or at least not my particular question.
I have a Vectra 1.9 CDTi 150 and it is fine, a different drive from our 1.8vvt petrol which I've passed to my wife and which I still get to drive now and then.
I'm very pleased with the 1.9 150 diesel - its performance (especially its acceleration) is superb and it runs really well and I'm getting good mpg figs so its running well and no indication of a problem as such. It starts first time as well, even on a freezing cold morning, the only thing I've noticed recently is that if the engine is already hot then on re-starting the starter motor can be a bit noisy for a just for a second on re-starting. It doesn't happen when cold starting, only "hot starting". I believe this might be to do with the dual mass flywheel and that sooner or later it will eventually fail and which is likely to be very costly (e.g. such as £1,400). Its my understanding that further "hot starting" will exacerbate it and make it worse thereby bringing forward the day when it will fail so I've therefore recently only used the 150 diesel for medium or longer journeys where the car will cool down by the time I start it again either much later that day or the next day, and where possible avoiding using the diesel for journeys involving re-starting the engine once hot (e.g. borrowing my wife's petrol veccy instead).
The diesel veccy is covered by a separately purchased warranty (i.e. not a GM one) but I'm anticipating that they would wheel out the old "wear and tear" get out clause given the potential horrendous cost involved and possibly also as it seems to be something of an achilles heel for the model.
Any words of wisdom would be appreciated.