Changed my Tourer struts today
 

As old wills say "being of sound mind but feeble in body," I've found that heaving the tailgate open was getting slightly more of a struggle so I've just fitted new ones from here.
Cost just £18.95 and what a difference it's made. Just have to open the latch and it lifts zomby like. Of course it's more of a struggle to pull it down now, but it seems you can't have everything. I was also surprised to see that it will hold up even when just one strut has been fitted. Recommended.