My favorite build in this is 26ga SS, 3mm coil, 6-7 wraps, comes out at about 0.6-0.7 ohms. Vaping it at around 30W.

Any wire works fine, depending on how you like to vape. For 28ga kanthal wire, I'd probably go for 2.5mm coils, 5-6 wraps should get you around 1 ohm, and vaping that somewhere around 20W should be great.