Spring/Suspension calculator:
http://www.mx-tech.com/ . Give it a try.
A lot of guys have their suspension professionally done. I didn't with mine. I used the calculator, replaced the springs with the recommended. Played with clickers until it felt right. I think the suspensino is still stiffer than you might find on the 450X model. I do Enduros, HareScrambles, and track riding. The setup I have now is working good. I think I still get beat up a bit in the woods/tight stuff...but to keep the bike ready for the track jumps, it's a sacrifice I can live with and it works for me.
Hope this helps. Good Luck!