It's not anywhere near as bad as people make out (as you probably know) the torque steer is blown out of proportion and the car does understeer on throttle but is due to the total lack of RARB (most likely left out deliberately by GM due to the target market).
With a RARB the understeer is massively reduced and as standard on the 18" wheels the car is well damped, the only time I have noticed an issue is on a particularly wavy section of back road near me or a coupe of sections of the 'ring. It is out gunned buy the current gen of hot hatches now though.
I've had the joy of driving the entire VXR range around Donnington, Corsa, Astra, Vectra, Meriva, Zafira and VXR8.
The best car believe it or not was the Corsa, so chuckable and quite a bit of fun, a surprisingly quick car, think its also around 1:31 on Top Gear lap times so above that of the GT86 which from my time in it I can believe it was a quick little car on the track.
The worse car was the Vectra, even when piling on the power to overtake in a straight line on the back straight, you need the muscles of Arnie to steer around the car in front due to the immense amount of torque steer, it really did illustrate how 300BHP through the front wheels was nothing but a joke, in the corners is was hopeless.
The Zafira and Meriva, were just a joke, just nippy MPV's with some ability, but I was just hoping their was self destruct buttons inside.
VXR8 was nice simply as it was RWD, but the diff was causing big issues on track, if you went down the gears whilst slowing for a corner, the back wheels would just lock up if you were not careful, was a big case of WTF, even trying to be gentle it was hard to not cause this issue, a big shame as other than that it was pretty good, though its weight could be felt.
The Astra, well it sat in the middle of the Corsa and Vectra, the Corsa was definetely the more capable car in the corners and more fun, but the Vectra was pretty damn quick in a straight line. It did have torque steer for sure but not as bad as the Vectra. There was definetely plenty of understeer present, but again not as bad as the Vectra.
If I was buying a VXR it would be the Corsa every time, it was simply the most fun out of all of them, though the Astra was pretty decent and certainly had the straight line ability.