UKC

Anyone tried one of those u-shaped shock absorbers?

Or would the old style sprung saddle be more effective?

Ive not tried one but have laughed at it. They are going to move around quite a lot laterally as well as vertically.
You can get the traditional sprung saddle or suspension seatposts, either of which are going to be better than this spring.

The Cane Creek eesilk+ seatpost is great and does what I think you are looking for. There is also a new saddle with a similar idea - Bikeyoke Sagma.

About a year ago I bought a Brooks leather saddle with springs. After about 500kms, it was nicely broken in. I've stopped wearing padded shorts completely. Longest day so far: 160kms, narry a twinge. Worked perfectly on road bike, MTB and now on my cargo bike. Gives a plush ride even without suspension.