I have also been a member of both for years, this gives more sites to choose from and more CS/CL five unit sites around the UK. I agree with the comment on the formality of the pitching - for example the 2 sites at Sandringham separated by a short footpath, and it used to be the same at Malvern - the same entrance shared by C&MC and C&CC and Guides camp (although it is a while since we stayed there so things can change). I would also expect more hard-standings at C&MC sites, for example just back from Clumber Park where there are about 50% hards, and the site was full over the weekend with about 40% motorhomes, 1 folding camper and 1 trailer tent the remainder caravans. In terms of the overall cost you get access to different club insurance quotes, breakdown cover, foreign site/ferry bookings, and of course 2 'comics' each month in addition to your invaluable subscription to Practical Caravan!