I've been using them off and on for the past month... when I realized I had millions of CC flannel patches from my benchrest days.
Compared to organic ball cotton and make-up pad cotton, I really don't perceive much of a difference in flavor. They wick about as well, and last about as long as KohGenDo, Muji or Shiseido pads... but do not wick quite as well as rayon - sort of splits the difference.
They are thinner than make-up pads - and if you choose to roll them around a mandrel, you can produce a sort of "hollow tube" affair, which I've not decided is actually better than just a normal roll-up.
I have an inquiries with a few cleaning patch manufacturers (interesting timing coincidence, eh'), requesting information on any chemical residue I should be aware of... bleach, hydrogen peroxide, etc etc.
I can't taste anything unique or obvious... but that doesn't necessarily mean anything. I'm old, with an equally old "taster" that can't really pick out the finer nuances of a flavor.
I'm also looking into obtaining a sample of, and more specific information on, Butch's "Triple Twill" patches.
I'll post in this thread, Darryl... if I can obtain any new information. Stay tuned. ;-)