I've tried a few configurations in my 97....

I ditched the stock piston seal and used JM's. That gave a roughly 30-40fps more alone. I replaced the stock spring with JM's Tarantula 33 coil with spacing and it gained another 10fps+. I've recently installed a spring from a Quest 1000 just for kicks and it worked so well, I left it in! A little sanding down of the guide is in order for the spring to fit. Although I lost some fps with this set up, it's much smoother and still gives me 830fps with JSB Exacts.