I already am hooked on the blue foam.
Is this newer filler better than the blue foam?
It isn't really a proper comparison. The reason the blue foam (or Fluval) worked better in cartridges is because standard polyfill tended to trap liquid below the top, while other methods (blue foam, Fluval, PTBs) allowed more liquid to flow more freely to the atomizer bridge without leaking. (In smaller carts anyway. This didn't work well in XL carts/atomizers because there was too much liquid over a larger volumetric area for the material to be able to prevent gravity from doing its thing.)
The design of these cartomizers makes that problem irrelevant. The issue with carts/atomizers (and most other cartomizers) is that liquid has to travel through the cartridge filler to the top, transfer to the bridge, then to the wick, then to the coil to be atomized. It does this by the bridge pushing into the filler and soaking up the liquid, then the wick soaking up liquid from the bridge, then the coil atomizing the liquid in the wick. But if the liquid doesn't rise to the top of the cart easily, the bridge can't get at it, so it ends up drying out long before the cart is empty of juice, which is just trapped below.
These cartomizers have a vertical dual coil design that runs through the center of the filler material. That means that, at most, the liquid only has to travel from the wall of the carto to the coil in the center, which is only a few millimeters, and it does this from all sides, not from the top down. Because of this, the coils are also able to atomize liquid from all sides; more surface area to feed the coils with juice means more vapour produced and a shorter distance for the juice to travel. There isn't enough filler for the juice to become trapped in. Plus, there's no bridge (it's not needed, the coils have "socks" covering them to keep them from burning the polyfill) so the coils have more direct access to the juice.
In short, you don't
need alternative filler material. The polyfill works perfectly. You could say the filler works better than blue foam, yes, but it's due mainly to the design, not so much the materials.