For me to make a statement that Eibachs puts the most effort into springs I would have to go to
EVERY aftermarket spring manufacturer in the world..then I would know.
I highly doubt anyone here has done so.
I run a german company here in the US, so I know the in + outs of German Quality, and yes it is second to none but still I haven't been to others so I will restrain myself into making superficial statements.
eric