Ours is the 7.5 tonne Mercedes Vario 814, 7.8m total length with the back box. In the UK we use the RAC via the Camping and Caravanning Club, mainly because we have other cars with them and want the full recovery service where we can choose whether to be taken to a garage, or to our destination, or back home. ADAC only offer transport to the nearest suitable garage.
Last time we went abroad I signed up with ADAC, they were the only ones able to cover us for Morocco. As our next trip abroad is not till 2012 I've cancelled ADAC for now. In September next year, when the RAC cover expires, we will drop that and just use ADAC. They cover Europe including all of Turkey and also the North African and Middle Eastern countries bordering the Mediterranean, so will be ideal for us
I don't think signing up or renewing is a big hassle, so far I've done everything by email with no problems.
AndyC