Yes I've found that they tend to work better (read: as they are intended to work) after a good cleaning. Perhaps the filler doesn't expand inside the large end of the tube as they should initially, or there's some kind of chemical residue left in them from the 'factory', or maybe just the moisture of a complete cleaning primes the filler better. :shrug:
Much like there's not much difference between colored pencils and crayons.
Mn-puffer:
My cleaning advice:
I. disassembly
The way to clean them is first get they carto wet - pour some water over it just to get the filler moist. Then take some tweezers and gently pull the filler out. The filler being wet is important because dry it will pull apart some.
II. cleaning
Soak the empty cartridge in warm water, or for advanced cleaning use some pga or an ultrasonic cleaner (although I don't do these things). Then unwrap the filler, notice there's a tinier, thinner cloth at the center (don't lose this

). Wash the fillers thoroughly with some hot water and soap (I suppose there's good kinds and not-so-good kinds to use, but hey, ymmv). Rinse thoroughly being careful not to stretch the bigger filler very much, because it will warp if you're monkey pawing it. It's an excellent idea to give it a distilled water rinse down after this, otherwise you will taste icky faucet minerals for a good while. Dry by pressing between two paper towels, or placing on hard surface and pressing with paper towels, or using a blow drier (be cautious of flying fillers!). Rinse out the cartridge, give it a distilled water rinse, and blow it out from both ends. Then use a blow drier or let sit upside down overnight.
III. re-assembly
Insert a drinking straw over the cartridge straw. A McDonald's red straw is easy to find and only requires a slight enlargening on the end with a pen/tweezers/whatever to fit. Other straws that would fit all the way down are preferable, but I don't have any. Wrap the filler around the straw semi-tightly being certain to keep the mini rectangular cloth-like filler as it was originally (long-wise vertically against the cartridge's straw) and gently twist down into the cartridge until the top is flush. Use tweezers/whatever to push the rest of the way down into the cartridge until it stops. Hold the filler down with the tweezers/whatever and gently twist the drinking straw out of the cartridge. Gently pack down filler a little more, and you are done
I'm thinking of doing an illustrated version of this sometime, if anyone thinks it would be helpful.