The best way to know if a dealer is good is to get a complicated problem with a purchased product and then see how they resolve it.
As I've not had any problems, except for a mirrored infinity stop (I got a new one for free), I can't say how Linhof Studio can help then, but in all my dealings with them I've got nothing but excellent service, and they do seem very knowledgeable. Most Techno users I've stumbled into have bought their gear there, which means that they probably have sold many systems and have good experience with it and probably helped with support issues. I've bought most of my components second hand, but the new parts to my Techno system I've got from Linhof Studio. For these type of products I rather employ an expert dealer abroad than use a local dealer with limited experience of the system.