I just got my new GTS Expedition seat in the mail today! I'll let you know how it is. The stock OK Trident seat was killing me and I went through a similar issue trying to decide. Finally enough positive reviews for this seat made me pull the trigger. It cost a little more but my ass is worth it.
I didn't get it from the online store here I am sorry to say, being that I had a credit at another online merchant. That being said, they have it and from what I hear it is well worth the money.
http://www.kayakfishingsupplies.com/...on-Seat/Detail
Dan