They're the best option I've used as far as replicating an ice like feeling. As previously mentioned I've used the old Tuuk Rocker and I've also tried rockering the wheels on a flat chassis and prefer the Sprungs. As for durability, I used my original A6 chassis for about 4 years before I retired it, but probably went through at least one complete set of rocker arms during that time. There were a few reasons for this: The knuckles on the A6 arms were a weak point on the original version. The new version has beefed up knuckles with tighter tolerances.When I first started using them I didn't realize you had to condition them or clean them every once in a while (about once a month is good) and when the plastic gets dry it's more likely to break.I'm bigger/heavier than the average player and was jumping over the boards on changes like I do on ice, but now I just go through the door to avoid putting extra stress on the knuckles.Also, if you don't take apart and clean the chassis on a regular basis the dirt that gets inside will cause friction and wear down the part of the chassis that holds the arms as well as the outside of arms themselves. This isn't as big of a problem where the rear arms are connected as the connection point is deeper. It's more of a problem in the front where the connection point is shallower - if you don't clean them regularly then they'll loosen up quite a bit after a few years. You'll still be able to use them, but they won't be as responsive as when they were new. If you're using them outside you should clean them even more often as the dirt you'll find outside is generally more abrasive than the dirt and dust on indoor courts. With all of that said, I still wouldn't move to a flat chassis unless I had no other options. None of the new beefed up rocker arms have broken on me in the few months I've been using them. They're wearing well, but I also clean and condition them about once a month and haven't jumped over the boards with them. The tolerances are tighter and the springs are stiffer so they also feel faster and more responsive. As far as Justin's comments, I have to respect them as he has years of experience designing roller hockey specific products. I too felt a bit unbalanced on one set I had (I've had a few on a few different boots over the years) as they were mounted too far forward. Once I was on a pair that was properly mounted the balance wasn't an issue. They have to be mounted just right - you or the shop you take them to has to mount them exactly like the instructions state - 1/4" back of center. I doubt this was Justin's issue since he'd be able to mount skates very well with all his experience, but a mount that is off will certainly cause issues. A well worn chassis that hasn't been cleaned will also provide more play - the older models in general will provide more play as the springs aren't as stiff. If you use wheels that are too soft with Sprungs they will feel slow. Sprungs need harder wheels for the suspension to work effectively. I first tested out the Sprungs with outdoor wheels and was happy with them, but when I first used them indoors I was a bit disappointed as it did feel slower. This was corrected when I put on harder wheels. So I still recommend them, but for best results: Buy the newest model. The knuckles are beefed up, the plastic is supposed to be of higher quality and the springs are stiffer.Clean them and soak the plastic parts regularlyDon't hop the boardsGo with harder wheels than you'd use for a traditional chassis. I always use the hardest indoor wheels I can find and even use an outdoor wheel on the back as that wheel always wears fastest.Make sure they're mounted 1/4" back from centerThe Marsblade Wicked3Aussie mentioned is also supposed to replicate an ice feel. I'd be curious to try that as well, but it's even more than the Sprungs at the moment, but do come with wheels and bearings. I noticed on their Facebook page they indicate they're launching in Canada in the summer of 2014 (they even had some ads at the MasterCard Center in Toronto). Perhaps the price will come down a bit and there will be a chassis only option at that point. Since I'm already comfortable with Sprungs I don't know if I'd shell out the coin to try Marsblades though unless I heard from other Sprung users that they were significantly better or if Sprungs were no longer available. So I can see why people who are already comfortable with whatever chassis they're currently using wouldn't switch to Sprungs. In a case where you're looking to replicate an ice like feel then the Sprungs and Marsblades are two options to consider.