I replaced all the springs, shocks, and tires on my 04 a couple of months ago when it was at 80k with FJ springs, KYB shocks, and Michelin ATXLT2 tires and the ride is excellent. Then again, all those were pretty worn out (especially the tires) since it was original since vehicle was new. I'm sure all 3 contributed to the now nice ride but can't really say which is the major factor. I had KYBs in my previous car (MDX) as well and they rode very nice. I didn't want the ride to be too stiff so I didn't go for the Bilsteins.
Thanks Chris for the idea of putting FJ springs. I didn't replace the bushings but the car still corners great and almost no sag with full load.