This is the original seat designed  for the M5 carbon high racer.  It may be able to be modified for other recumbents as well.  I know a lot of high racers have them.  Everyone knows this is the fastest seat made, except for the brand new version being created by Railgun.  I bought this right before my RA started attacking my soft tissues and robbed me of my ability to ride fast.  You may not know that it's also one of the most comfortable seats out there.  You can carry a lot in the tailbox.  Cool as hell.  Yours for 600 plus actual shipping!
 
Link to my dropbox with photos:  
https://www.dropbox.com/sh/gqpo6ah4zhqp3tv/AABsEr1Fxx5_bNEPA93hvqpMa?dl=0  

I might be able to answer, even though the thought may be stale by now. You don't sit in this seat as much as you sit on it. I have used this specific seat, and later purchased one from Kent. (didn't realize Greg was selling) Anyway, the seat will accommodate a very wide range of riders. I am about 6', but a rider 2 or 3" taller or shorter shouldn't have issues IMHO.