Definitely check out the sprung thread. Its a long read, but the info you gain from it is insanely helpful. To sum it up, with the sprung chassis, you get the benefit of 4 80mm wheels with regards to speed but you have unmatched maneuverability which is supposed to be the most ice like feel of any inline skate (i'm only an inline guy). I instantly adjusted to the changed and haven't even contemplated ever going back. Now instead of looking at the latest inline skates I'm looking at Ice skates because I KNOW I'm instantly ditching the stock chassis and putting on some sprungs. Another added benefit is the durability and replaceability (don't think thats an actual word, but...). At 6'2" 250lbs, and a wild skater, I've destroyed many an inline chassis. With traditional inline chassis, as soon as you go too fast into a board or whatever else, you're out at least one chassis, maybe two. With sprung, on the odd chance you actually break one, they're much more replaceable, and MUCH MUCH more economical (as well as easily) to fix. And while at some point it does get slightly annoying to explain what exactly is attached to the bottom of your skates, its easily balanced out by the performance as well as joy of spreading the mojo of the sprungs. Speed, maneuverability, and overall GREAT feel of the sprungs is second to none. They're awesome :)