Hi Roger,
I am a member of a club, albeit the wrong side of the water for you, but I am also one of the first members to join TSG when it launched in 2008.
From my perspective, I get the best of both worlds. I am very happy with my club membership, now spanning 15 years. I am now a member of the General Committee and Ladies Committee. I love the membership, can play whenever I want and enjoy the clubhouse facilities, as well as enter all the comps and try to reduce my handicap (going the wrong way at the moment - must try harder).
However, I wanted to play other courses and meet other golfers in the local area, as well as bring them to my club at greatly reduced fees and I regularly host games for the guys and girls. I have made a lot of good friends by being a member of TSG and am a member of the group SES and have also played with some of the famous Epping Bandits who are great company.
So - I would probably emulate Steve's recommendation at this stage and join a few of the Epping Bandit games and get a feel for what we are all about and you won't be disappointed.
If you decide you still want to join a club, there are great deals to be had on 5-day memberships and there is always heavy marketing going on, so the world could be your oyster.
Enjoy