We call them 'studded tires' over here. They've been outlawed in most states, due to them tearing up the road surface, but yes they do grip. Used to have them in my snow tires when I was younger, and then I remember pulling them all out with a pair of pliers when they were outlawed.
Now we have to depend upon the new tread designs and tire compounds for the dedicated 'winter' tires, often referred to as 'ice' tires, with Michelin X-Ice, and Bridgestone Blizzak, being the most popular.

 

I have to add my 2 cents worth to this thread. When you are driving your XK/XKR in good weather or bad; on good pavement or bad; you need to remember one thing. Your expensive vehicle and your safety, to a great extent, are relying on 4 patches of rubber about 15" x 15" more or less that are meeting the pavement.

So, the bottom line to me is to acquire tires that are made to the recommended specifications of the manufacturer (Jaguar), either all season or summer tires. In your case given that you rarely if ever take your vert out at temperatures below 50 degrees Fahrenheit, get the high performance summer tires of your choice and check the date of manufacture on each tire before they are installed.

 

Wait till the new owner joins this forum and finds how you treated this car worse than a rental.
Did the ad say 'gently driven cross country through the rust belt in winter'?

 

Wow.

This thread has got everything.

I don't even know where to start, between the egos, shitposting and cringe-worthy arguments.

But let's get one thing straight, they are tyres, not tires.

 

Not only has this thread gone well beyond the original question, it has degenerated into personal insults and posturing from some members who should know better.

THREAD CLOSED

Graham