I started with no-name silica today, and thought it had a taste. Then I pulled out this baker's twine (out of the package and into the coil; no stops on the way) which I'd bought in anticipation. I'm very happy with it. No cotton flavor to speak of (compared to unbleached cheesecloth and cotton yarn). So what silica are you happy with? BTW, I do my cotton with a thin sleeve of ss mesh just under the coil (like a 3/8 x 1/2 square)
THAT'S CHEATING!
I was trying to get away from SS mesh due to the chromium scare thing, so I went through a bunch of wick experiments. I know you're the experimenting kind, so you can probably relate. And I've never really cared for the (to me) muted flavor with a SS wick in a genny anyway.
I've seen your builds, and the SS over cotton is a good idea, but it means you aren't really going to taste any wicking material you use. You could use hemp, it wicks well and will supply that SS with plenty of juice if in a dripper. It's not so good in a genny. It requires a U-wick to wick well. I had one successful build, tried another 5+ times and gave up.
Anyway the silica is from Germany. eBay vendor vaporbase-de. He ships internationally for cheap.