Am assuming they mean "track" tyres... My GT3 was on "Cup" tyres and so have some experience to share (basically they come with about 4mm of tread when new and a compound/construction more suited to, err, spirited driving hahaha...)... Yes, they are lovely, in the right conditions, which do not really include much in the way of winter driving... If you are going for cold, wet, snow, ice etc then I would definitely recommend a second set of wheels/tryes to pop on in the colder months... As a rule of thumb, I swapped mine over (summer to winter) when I felt it necessary to turn on the heating and then back again when I felt I could turn off the heating... I think the suggestion was 6 degrees C (or less) air temps was a good swapping point... But you can check with the manufacturers...
My cup tyres were Michelin... I used Pirelli Sottozero winters...