I have to raise a hand in support of AOPA UK. Not a lot of people know that they also have some clout with the CAA licencing department, so when you've finally exhausted all options and are about to file a formal complaint they can step in and try to resolve issues. They resolved a five week delay and a stand off over lost paperwork to less than forty eight hours when I had to change my JAR-OPS licence to an EASA one.
As stated above. When it comes to having a voice in the future of GA they are the only organisation looking out for all aspects of our operation. The LAA and others are fine for their corners but only AOPA can speak for all of British GA in Europe. I cannot believe that some people regard the membership cost to be prohibitive when it represents less than one hours flying in most GA types.
Remember that most professional pilots pay to be represented by one or other of the available organisations (BALPA, IPA or Honourable Company) so what's wrong with GA pilots doing the same.