i just rode one of those for almost 2 years of very hard, high flying rides, in some of the roughest terrain known to mankind !!!!!!
it was never touched settings wise, except the sag, rebound and compression setting screws that are on it, and it will need no further internal or spring adjustments done to it, it was an awsome shock and performed flawlessly, as it would on any 450r from the factory with any weight rider or riding style
only reason i sold mine was to try out a "works ultracross" i got
/\/\/\ hope that wasnt a mistake, thats how good these shocks work
it will need ken oconnors bushings to make the top a 5 minute bolt job, but fits perfectly with the same ride height.
but will also require cutting the left front mounting tab off the rear fender and its mate on the frame, and will rub the airbox, as the 400ex's do
these are awsome shocks, as they come, and a good buy for that price !!!!!