The RAS came in this week along with the 5100s, so I put all 4 5100's in took it for a test drive and they do indeed help with the wheel hop. Came back from the test drive and installed the RAS, and took it for another spin and here's my review. But first, I should point out I bought them in lieu of air bags for pulling a heavy toy hauler. The reviews were that when unloaded it didn't effect the drive that much, while loaded it allowed you 40% more hitch weight.
I'll start off by saying there is a slight driving difference when unloaded, but it's not necessarily a bad thing. The best way to describe it is it feels like a "sport mode". Everything is a little stiffer. It does a really nice job of eliminating body roll in corners (very pleased). And the best thing I can report is it completely eliminates any axle wrap when you nail the accelerator to the floor from a stand still. In terms of when it is loaded, I didn't take it for a drive but I did put the TT on the hitch, and I'm super impressed with the lack of squat. It essentially turned my F150 into an F250 in that respect. I've got both and the squat is about the same now. All in all, I'm really impressed with these things. If you don't mind a "sporty" type feel I wouldn't hesitate getting these things. The 5100s and the RAS has turned out to be a really nice combo.
If you're thinking about air bags for any reason give these things a look.