Is the filler replaceable or do you just keep using the same filler?
After messing around with different carts, I have found that the KR808D filler is actually removable!! Its just a barrel of polyfill wrapped around a wire with a piece of paper wrapped around inside the wire. the paper is actually what gives it the burnt taste when they go bad.
To get the filler out, just use a pair of needle nose pliers and grab ahold of the poly fill, it will pull straight out (Make sure you are only gripping the poly fill and not the paper or wire or the shroud around the wire) . I tired putting some wool nibs in place of the polyfill but do not have a straight up answer as to how it will do at this point, I just did it about an hour ago. It does have a slightly different taste to it, almost smoother if you ask me. I tried this two different ways, with the paper in place and without the paper in place. The one with the paper seems to taste better then the one without, I am guessing the wool is to close to the wire at that point and starting to scorch.
Anyway, you can get the filling out and replace it on the KR carts, I have tried the Smoke 51 carts, but could not get the filler out without screwing up the wire and also tried some of the other carts for the E8 which is just filled with paper it seems, again the wire is intertwined so it pulls the wire out along with the paper.
BTW, if anyone knows where I can get E8 blank carts or at least carts that don't taste like used dryer sheets, I would love to get some. I would up buying a bunch of carts from Japan and they really suck 8-o