Originally Posted by
dustin_j
I would also look into HLS shocks. They are made by GT Thunder and work very well. The essential shocks are $500 brand new, setup for your weight, riding style, and machine specs. They are not adjustable, but that is not always bad since the shock is setup for you. Like others have mentioned, if you buy used they probably aren't setup correctly for you, and this will compromise the performance. The new Elkas and Works also aren't really setup for you, and their valving is inferior to the HLS or even stock 450R shocks. I also agree with the recommendations to get used 450R front shocks and have them setup for you. Like mentioned, they are a great shock when rebuilt and setup for you.
For A-arms, I love Houser. They are very well made, and their regular travel arms give as much wheel travel as other LT setups and provide good leverage ratios. The slicast adjustment is also much easier to setup and change to suit your riding.
EDIT:
I would also recommend a GT Thunder linkage and rear shock rebuild. You won't believe how well your 400 handles after getting the suspension setup for you!