I swore my 08 Ferris is3100z came with the "upgraded" $500~ option suspension seat? I guess not, now granted the whole machine has suspension and rides nice, the seat has a spring in the very back but its only for the on/off seat kill switch.. I notice sometimes if i hit a big bump, the suspension takes the impact but the seat still jolts me up in the air. Why would a seat like this be a $500 ferris option on the smaller mowers and standard on mine if it still is not supsension? My 05 1000z seat looks like my newest one, but thats it, my 1500z has a black firm seat, little but i feel comfortable. The is3100z has a high back seat, but common, how could these be a $500 upgrade over the standard seats on lower models? my "seat" itself i dont think has any suepension in it anywhere.