You can't go wrong with cotton. But something to try out in the future is some braided hollow cotton wick with a piece of Ss wire rope wick in the center of the cotton wick. Its awesome
Mesh has a break in time also. Do have a slight twang of metallic taste? That taste will eventually dissipate. If your setup is to low of ohm and you still have the stock air hole it will be harsh. If your Nic level is to high with a Genius it will or could be harsh to you. Same goes with with pg level of your juice. Since you have air flow control open it all the way and see if that helps