I was up and out at 8am this morning to beat the kids on their sledges so I could try the winter tyres on my X5 on virgin snow. The verdict: absolutely brilliant. I bought a set of BMW 17-inch alloys off eBay for £200 and put Vredestein Wintrac 235/65 x 17 on them. My other wheels and tyres are 285/45 x 19 so I'm also getting the advantage of a much narrower tread. Most impressive is the way the X5 stops, despite its weight.