I joined. I thought the concept very sound, I believe in an organisation for its members to represent GA - it is badly needed in Europe.
Then one day I phoned AOPA, and explained I was interested in the current proposals regarding NPPL instructors. It was firmly explained to me that a committee existed to consider specifically this issue, and their considerations were really no cocern of mine. I persevered, very politely I might add, but got no where. The PFA were far more forthcoming. Sad to say I got the distinct impression that all the delays in the NPPL were placed firmly at AOPAs door - but then again apparently it was all their idea so I suppose they are entitled to make a hash of it.
To be fair, it was perhaps a one off bad experience, but I was sufficiently perturbed that I will not be joining again!