REDSHIFT ShockStop stem review*
It comes with a selection of elastomers so you can get the amount of movement you prefer. Zio set his up using the recommended pair and liked it just fine. No bouncing around, just a bit more "cush" when your front wheel hits a bump. No slop or wiggle when you hop over a bigger bump though you do get a bit of movement when you land or stand up and push down hard on the bars, but nothing like that when simply standing up on the pedals to accelerate or climb. You don't notice it until you hit a bump and even then it's very subtle, but still effective.
Overall, it feels like Zio let another 10 psi out of the front tire without any of the squishiness he'd feel running that tire at just 50 psi, so he's kind of happy that he failed to bring a rigid 10 cm stem down here just-in-case!
* Zio bought this at MSRP through the REDSHIFT website.