Ditched the suspension seatpost
We had been riding with a Thudbuster LT for about three years on our 1999 Cannondale RT1000. Stoker was not a very experienced cyclist going in. I thought a suspension seat post would help her feel a little more comfortable. She's also a fairly tall woman (5'-9") and I thought the extra 'throw' of the LT would give her a little more room.
Of course, I don't sit back there and couldn't really say if it helped her feel more comfortable or not. And, her not being an experience rider, couldn't really say herself.
Well, she's not a very smooth peddler and I could feel almost every stroke. She bounces around pretty much. I thought maybe the LT was exasperating her pedaling and contributing to her bouncing.
We moved on to the a 2006 Co Motion Speedster we used a Thudbuster ST. Though there is less suspension and also a little less 'effective' setback, she really didn't notice a change in her comfort. And there was still a lot bouncing going on back there.
Two weeks ago I put a solid seatpost with about 25mm setback, no suspension. Well, she loves it! She says she feels more connected to the bike, more able to sense my effort and - much less bouncing! And as tiny bonus, shaved about 180 grams.
I don't know, now I'm thinking a suspension seat post is not all that import for the kind of riding we like to do. I no longer have to worry about saving up for a BodyFloat, which was next on my 'to buy' list.