I didn't buy anything from them yet, but they seem to be one of the better online shops in Germany. As far as I remember, they even offer an international forum on their site.
dirk munziger is an awesome person, a bit harsh to trade with him but 100% professional, no problems with that man, I had buy him for 250 euros last week
I live in the States but I've purchased tubes from them before. Since I couldn't find an American or Canadian distributor who stocks SED 12AX7's I didn't really have a choice, but their service is good. International shipping can be rough of tubes though.