Tony,
First a big thanks for not going down the well trodden road of the nazi rant.
It is in my thoughts that the germans sell well is because sculptors always aquire the best period photos of the germans (of which there are millions easily bought over the net) and sculpt from there.
german military photos are brilliant and clear - a dream for sculptors.
Why is this important? We get brilliantly sculpted busts and kits showing the full force of the german soldier with clear details of webbing, weapons, awards and such.
For most other countires, IMO its hard to get good photos for sculpting purposes. Thus when some nationalities are finally sculpted, we get a bored face, a static pose and little detail. Thus, a model/bust that just doesn't stand out.
I really wish for other country kits (japan!) but until the sculptors give us something great that will stand next to a german sculpt, no one will buy it and stay with something, that even when painted bad will look like a master piece.
P.S. If anyone has seen a german heer in east front winter gear, please let me know