"I rented a Vauxhall that I couldn't turn the indicators off - it was ether left on or right on with no central off position.
I doubt that."
I actually borrowed a new Vectra in 2009, one of the last of that model.
I hated the indicators, if I recall they weren't a proper up and down stalk, but rather a thing like a cruise control switch. press it down slightly and the indicator went on, but the "stalk" didn't really move, similarly up for right but it was awkward to use. Plus Vauxhall's insistence that it flash >= 3 times before you could cancel and on mini roundabouts you never quite knew what state the indicators were at. Try to cancel the indicators and they go on the other way. Horrible to use.