of all the extras pushed by the dealer, the tyre insurance was the only one that i took up... i did remember that the cost was just barely above the price of 1 tyre and given that i have had 3 punctures in a 3 yr prior, made economical sense to me..
definitely didn't buy it for 500 quid for sure.. more like 250 - 300
can't remember whether it covered both regular/winters - heard different opinions here
have been using event tyres for quite a few years now .. unfortunately, am getting barely 8k miles on a set...not the X3 though