So, is it better than a Mondeo, then? It's the obvious question, particularly as the Mondeo is just about the finest family car there's ever been until now, anyway.
The first thing Vectra owners will notice is the significant increase in size. At 4830mm from stem to stern, the Insignia is even longer than a Mondeo, a car often criticised for its bulk.
The thing about both cars is that, after a brief period of acclimatisation, you soon forget about their size.
That's especially true of the Insignia because of the way everything seems to wrap around you, giving a feeling of intimacy without making you claustrophobic.
It's not as roomy as the Mondeo in the back, though. Legroom is fine, though you have to clamber over a high-ish sill, but the shape of the roofline nips headroom for a six-footer.
The Insignia's cabin is a classy place, especially at night.
In models with Flex-ride the instrument backlighting switches from white to red when you select the sport mode.
As with the Mondeo, the trim on the dash and upper doors has a different grain and feel to that lower down, where it needs to be more durable to resist scuffing. Both are now pushing so-called premium cars for cabin quality.
Switches are arranged around the driver in logical clusters and there's lots of in-car storage, in answer to one of the major criticisms of the Vectra.
There are the usual blind spots around the front screen pillars and with the sloping back window, but that's pretty much commonplace with new cars today.
The instruments look like they could have come off an Alfa Romeo and the centre console is angled at the maximum that allows you to get CDs in and out.
There's a perfectly sized wheel and an instinctive control layout, although it's not quite as instinctive as the Mondeo, either to look at or to use.