RacerTech Lowering seat bases for the RZR.

What is the primary purpose of the lower seat base, improved headroom for a tall person lowering the center of gravity? Or is there another advantage?

There is several advantages.. The centers are cut out for a suspension seat to allow more seat travel, they are steel so they don't break, and They lower the rear more than the front for a more reclined feel.. I don't know how they would feel with stock seats but The aftermarket seats set a little higher than the factory seats due to cushioning so the bases sitting lower also puts the steering wheel in a better position.