I wanted to try something different than the original three-flanged hoops on my toms and I had heard of these hoops as being a middle ground between the tree-flanged ones and the die-casts. Sonically, they indeed are. The s-hoop made the sound of my floor tom much more controlled. The decay became faster and some of the weird overtones disappeared. Also, I had an impression that the floor tom became much easier to tune and it stayed in tune longer.
I would have gladly kept the s-hoop on my tom if it hadn't been for one issue. Because of the shape of the hoop, I could not get a standard bracket mic mount installed on the rim. It's a serious problem in a gigging situation, where the sound guy might not be able to properly mic up your drum kit. I read somewhere that there are certain mic brackets that can be installed on the s-hoop, but I didn't feel like changing my entire mic setup just to accommodate for the new hoops.
Overall, the s-hoops are great if you're not going to mic your drums or if you're patient enough to find suitable mic mounts.