My experience on cotton for use as wicks (limited as it may be, I'm still new in the cotton wick dept) is that it all depends how the particular cotton has been "treated" (cleaned, processed, etc.).
I've read about somebody whose cotton tasted like a Bounce sheet, no matter how much they boiled it.
Another said it tasted like medicine.
I must have been one of the lucky ones, as I just taste my juice and only get a weird burny taste if it starts getting dry.
My first wick was from a cotton ball. I unrolled it, cut a strip about 1/2 inch wide by 2 inches long. Rolled it between my palms into an about an 1/8 inch rod. Preformed a 6 turn 32 awg nichrome coil on a 2 mm thick jeweler's philips screwdriver and slid it off. I rolled the end of the cotton stick so it'd be pointy and I fed it through one side of the coil. I pulled it through the coil with no trouble at all whilst holding the coil between my fingers, so it would not deform much. Installed it in my Phoenix clone and trimmed the ends so I'd be able to pack them in the bowl of the Phoenix. I wet the coil thoroughly, and made sure I had a small pool of juice in the bottom of the atty before I fired it up.
I was sold on the first hit. Thick cloud of vapor and tastes from my juice which previously had been very subtle, now jumped out at me.
I continued to use this wick until I got hold of some gauze, which I wanted to try, as the cotton ball seemed to go dry way too fast on me, and I'd heard gauze threads wicked great.
I did the same coil, picked apart my gauze till I had long parallel threads and got a bunch of them about 1/16th of an inch worth. I didn't bother to braid it or anything, just laid it crosswise on a 3" piece of nichrome, bent the wire in half trapping the center of the cotton threads and used this wire to thread my coil. Threaded the coil no problem.
This setup yielded less vapor, but more throat hit along with lots of popping juice (I love it when it does that!).
Both setups were from unwashed, unboiled cotton, because I'm lazy and impatient. However, they did not have any funny taste to them; no taste at all, really.
TL,DR: I suggest finding a different source of cotton, as they seem to vary widely in how they are processed. Try cotton yarn, or cheesecloth. I'm sure you'll find something you'll like! Cotton has won me over, for sure! Good luck!
ETA: Sorry in advance for the long post; forgot to say I threaded the premade coil, so obviously the dry cotton slid in pretty easily. Cotton swells up quite a bit when soaked! OK, I'm done now
