With you on the sidestep - I've heard that the cigarette lighter style connectors are very inefficient, which would explain ther overloads. I had to replace both the plug on a coffee maker and put in a heavy duty socket to handle the 300w it draws. I also had to install a dedicated 25A circuit for it, but that's another topic.
I've also had problems with some socket/plug combinations not staying connected very well. I'd love to see a better standard 12v connector. If the one that Dave has is indeed a european standard and it's anything like the one that camaraderie posted, it looks much better on both counts. I'd be an early adopter of a new standard, i.e. replace the plugs on my 12v appliances to match something like that and buy european when I can. We can do better.