If it had been a decision between the previous seatpost and a non-suspension seatpost I think I would have wanted to go with a non-suspension seatpost because I felt like I was being unexpectedly thrown all over the place when we went over bumps and when we rode at a higher cadence. That seatpost was the one complaint I had about our new tandem.
But I wanted to give the Thudbuster a try ... and so far (in approx. 56 km of riding with it so far), it's great! It feels ... "solid". Not so solid that there's no give when we go over a particularly bad bump, but more secure, stable, and thus very comfortable.
And for some unexplained reason, the saddle feels more comfortable, and I wonder if that has to do with moving it back 5 mm, or if it has something to do with the seatpost.