That's pretty slick! Do you know if you get the same articulation as compared to normal shackles?
Supposedly these can get as much or more flex regular shackles because of how far the spring is allowed to travel. But, I've yet to take her off-road yet to see how they really do. I'll know for sure how well they work in a few weeks.
I can tell you this though, on the road there is a lot less body roll (which is a nice thing :-))