As far as playing with them when they're in good condition; it's all upside. The downside with Sprungs is maintenance and to an extent 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 (launched 5 plus years ago) 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. Only two of the new beefed up rocker arms have broken on me in the five plus years I have used 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.
A member on another forum used both the O1 Marsblade and Sprungs and prefered Sprungs for playing:
Having used both and playing semi pro hockey, I find the sprungs to be ultimate in terms of performance. Gives your quick feet an edge. However reliability is another issue. I go through these like a faze. (220 5’10) I’m not a huge guy but I play competitive inline in Canada and im hard on my feet. My sprungs were done after 2 seasons. I used mars for one season and I didn’t like the way there “rocker” sat. Put me on the toes of my feet too much. Preference for me is the sprungs, however it’s subjective. I know players who swear by marsblades.
The high level players that have demoed the Marsblade R1 love that though; so it seems like a great option if you're willing to wait until Aug/Sept. In this YouTube interview, John Schiavo discusses the difference between the O1 and R1 as well as vs. a flat chassis:
The inventor of Sprungs has drawings of a new and improved Fizix chassis on Facebook, but there's no telling when or if that will be available.