The sliver 5100's are the same as the yellow and blue. The only difference is the 5100 are for 0-2 inch lift.
The 5100's are gas shocks, aren't they??
I have approx. 70k miles on a set of blue/yellow Bilsteins. How many miles can I expect from them. They seem to be doing fine but detecting worn shocks is tough as they usually fail slowly. I drive on a lot of rough roads.