I think the GR-2's are a direct OEM replacement shock, I think
correct me if I'm wrong.
Check
www.tirerack.com they have the GR-2's there for about $250.They also have the AGX's there for around $400.
The AGX's are adjustable from Street(soft) to Race(hard). Both shocks should work fine with stock springs or aftermarket lowering springs, but no more than a 1.5 inch drop for the AGX's, they perform their best in between their.
You also might check with
www.groupbuycenter.com they have a group buy their ending 4/25/01. The AGX's for the P10's are $370 shipped in the "continental u.s." plus they're dealing with
www.coximport.com which is giving it a "limited" lifetime warranty, whatever that means, you should probably call them lol so good luck, let us know how it turns out.