Since this thread has come back, again ...
If anyone is interested in suspension seatposts, this was published about a year ago but probably is still valid. But, this site is oriented more towards touring, thus this might offer more suspension than most long distance pavement riders want.
https://www.cyclingabout.com/best-su...g-bikepacking/
I have a sprung Brooks saddle (Conquest) and 32mm tires on my rando bike, that is all the suspension that I need.
But I do have a cheap telescoping suspension seatpost on my heavy duty touring bike that often goes off road or on gravel.