I am still waiting to hear more about the Gold Line's. I guess the current ones are not for use on the P5, but they should be out soon. I think they were going for ~$140. And they are made by teh guy who made the original Eibachs, so there does not seem to be a quality issue. Check the Rims/Tire/ Suspension board for a thread on them.
But then again, everyone seems to love the Spool's!