I'm in the process of lowering my 2003 Outback and bought a set of the KYB shocks for the Subaru Legacy. When they arrived however, the left front is a GR-2 while the right front is a Excel-G. The part numbers are what they are supposed to be and I don't care too much about the color. I can just paint them.
But I'm concerned that one side will not perform the same as the other. KYB insists that the difference between GR-2 and Excel-G is just the name and color. But I read some forum posts that one is stiffer than the other. And doing a unsophisticated side by side test (stand them both on end, and lean on them at the same time) the GR-2 does seem slightly softer and does not return to full extended position as quick as the Excel-G.

Anyone know for sure if there is really any difference between the two besides cosmetic?

From the horses mouth (kyb):

"We apologize that this is a bit confusing. Both products are identical, except for the product name and paint color. KYB sells products throughout the world. Some part numbers fit vehicles from various countries that share the same chassis platform but, have different nameplates. At one time there were several KYB brand names, but we are now moving toward one name and color. So in the future all new part numbers will be branded as Excel-G and have black paint."

 

So there is no longer a difference, but there are probably differences from the older vs newer stock.