so I have converted about half of my ce3's to cotton, Going back and forth between silica and cotton I have noticed much more irritation with silica, you can sometimes even feel the strands hitting your tongue, after they hit they not big enough to feel directly like a hair in your mouth but the irritation is there when you move your tongue around, one c3e3 was particularly bad just after the first fill, constantly throwing fibers popped it open to find a disintegrated wick and loose fibers at the foyer (for lack of a better term) to the tube that leads to the drip tip.
I have only found one downside of cotton, with especially sugary juices, like Highbrows "buttered rum and then some" I only get about 3 mls before performance drops off, they just seam to plug up, they don't burn just stop producing much vapor. fortunately I am getting pretty proficient at re-wicking and with 700 yards of wick at my disposal I will not be running out any time soon.
with less sweet liquids I have yet to have one problem with a cotton wick. all going strong still.
I pulled apart all my silica ce3s and I am converting them all now,
a big up side is re-wicking and coiling costs almost nothing compared to buying new when they die, my vaping cost just went way down,
)...I've noticed when I pull my wick/coil set up for a change the cotton under the wick is hard, it's like the sugars in my juice have been slow cooked (to be expected) and that has created a "plug" that I imagine stops the wicking to where it needs to go...I know what you're thinking, why would this be an issue endemic to just cotton...I don't think it is, I have to remind myself that I got 3-4 "good" days out of a ceramic set up on my Ody and just dealt with it, but now I get all bent when my cotton equivalent only lasts 10 days
)...point I'm trying to make is, if you make a wick from rolled cotton (or a cotton ball) and it sucks, don't write it off as "it doesn't work"...on the one I'm vaping now I made what I thought was a stupid loose wick as far as density goes (don't know why I try and pack as much cotton as I can into the wick hole 
)...seems the deal is (so far) when using rolled or balls make your wick then twist it as tight as you can...at it's tightest it should be about 2/3 the size of the wick hole you are putting it in...(I reserve the right to discount my aforementioned size/density method as complete crap at any time, but it worked this time...)
