Check here if you want some more info on the Koni 86xx setup.
Update - Nissan Road Racing Forums
This guy Veilside makes custom housings for the koni's for S13 & S14. Get some Ground Control coilover setup with whatever spring rates you want. Price for the whole setup comes out comparable to a set of OTS coilovers. I had a set of Koni yellows on my Integra and loved them. I can only imagine the 86xx series would have even better damping/control qualities. The Koni's are also re-buildable and can be serviced without sending them halfway around the world. Plus you get to buy American to help the economy LOL