[bmwloco]

Frank,

First, why are you running different rear wheels? 912's, as a whole, are very balanced - good power, weight, and balance. Once you change things, you add expense.

Aside from that, your shock options are Boge, Bilstein, Koni or KYB.

In some cases, Boge just aren't available.

Expect to spend $350-500 for Bilstein or Koni. Depending on your car, you may or may not be able to run Bilstein or Koni's without a adapter plate change.

By far, KYB shocks are the least expensive and most painless way to go. They can be had for about $150 for two struts and two shocks. I have them on my 912 Targa. They work well, though some folks may blanche at the fact that they're white. I can replace my KYB's 4 times for what I can buy one set of Koni's or Bilsteins.

If I can offer any advice, stay as close to "stock" as you can and keep it simple. Your 912 will last a lot longer that way, and serve you well.