RealOEM.com * BMW E53 X5 4.4i Front Spring strut/Carrier/Wheel bearing

What's the differentce between the sports suspension settings on the struts?
Just different stiffness?

I'm looking to get some new ones, I'm hearing some clicking when I hit bumps thinking these are to blame.

Thanks

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02 BMW X5 E53 4.4i Sport
07 BMW X5 E70 4.8i