Mikael,
Read this article for a good primer on shocks:
http://farnorthracing.com/autocross_secrets6.html
The Koni's appear to be one of the best values out there for an 'inexpensive' quality shock. I bought Koni's for my car from Pantera East, and will put them on as soon as I finish my engine rebuild.
Call Dennis and order some stiffer springs for your shocks. That should take care of your problem. I'll PM you with a document I put together with the spring rates that different people run on their Panteras.
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