Swift replied to a question I had about the progressive portion. This was what their reply:
"yes the progressive portion of the spring acts like a helper spring. It is fully collapsed at static height. And yes it is a linear rate."
he also mentioned that Bilstein sport would be the best way to go. I guess he was getting a lot of people calling to see what higher performing shocks/struts would be best. He contacted Bilstein and found out GREAT news. You can get it custom valved for FREE when you order them new. I contacted AJUSA.COM (probably Bilstein biggest distributors and cheapest price actually) to confirm, and indeed it is true. I asked what info they need. He said: spring rate (we have), curb weight (we know already) and corner weight (i emailed swift to get this info). With this info we can have custom valved high performance struts/shocks for our cars!
Now I need to find a way to buy these< ran out of money! lol