I ended up getting a good deal on a Ritchey WCS Vector Evo Streem saddle and WCS Carbon Link Flexlogic seat post on eBay so I gave it a try on my bikes this last fall & winter.
First impression: This combo is VERY light, the post and saddle together come in at just 341 grams combined. Installation was simple, the mono rail system is simple. It's nice that the Streem saddle has two wings at the back as part of the suspension system, so you can strap normal seat bags to it. However, as there are no rails, it's not compatible with Ass Saver mudguards.
On the first few rides, the seat angle was slipping over big bumps. After I got home and put some fibre grip paste on the clamp the top of the post, and torqued it to spec, no more problems.
The saddle and post combo does seem to absorb a lot of road buzz on my CX aluminum frame bike very nicely. The advantages weren't quite as noticeable on my carbon bike, presumably because the frame is already absorbing a lot of the buzz. However it did still offer a weight savings of nearly 60 grams over my Fizik Aliante R3 K:ium saddle with 3T Palladio LTD post which comes in at exactly 400 grams.
For such a hard saddle, I had no problems at all with comfort; of course this is highly personal, and I don't tend to have problems with any saddle or chamois combinations, I guess I have tough skin.