I joined mainly to get access to the EPC, an added bonus has been the excellent club magazine, I also received a Mercedes Classic magazine despatched by MB, which is less regular, but a bonus. We have attended local shows with the club, where the club marque's have been used for a very professional and enjoyable day.
My join/not join benchmark is down to, the MB membership is the same cost as the Corvette Club I am also a member of. The Corvette magazine is not a patch on the MB one, they offer little else, so in that respect the MB club is good value for money.