... The only issue I had was the depth of snow... It was over the bottom of the bumper! Once moving I had no problems at all. Got slightly stuck 3 times, all of which I was trying to reverse up an incline.
Same here. The problem areas were where the roads hadn't been touched (including our road, so game over

).
It wasn't a case of needing winter tyres. The Omega simply didn't have enough ground clearance to go anywhere!
Once out and about pretty much anything was passable on reduced tyre pressures, plenty of weight in the boot and a bit of care. I got stuck a couple of times and wished I had some snow chains but a bit of shovelling got me going again. No way would that experience be worth a couple of hundred quid's worth of tyres and a spare set of wheels cluttering up the place!
I may well invest in some snow chains before the rush this year.
Another tip - get a couple of sacks of water softener granules to weigh down the boot. They come in handy if you get stuck too!
.. and having 8mm of tread on your tyres will make a big difference to tyres down on the wear indicators. If your tyres are getting low, change them before the really bad weather sets in.
Kevin