When questions my insurance company said there was not a time limit but if I made a claim regarding the rig and it was found to be in poor condition I would not be covered. Pretty hard to check the condition if it was all at the bottom of the Solent somewhere 😉
I use Continental All Season Contacts, seem to do fine, wear wise, and handle in both warm and cold, I drive a Volvo V60, mainly motorway at moderate speeds.
My lewmar windlass works well with octoplait and the long splice that joins it to the chain. The long slice is tapered and is very easy to do yourself.