I have built about 15 coils in the last two days experimenting with various ohms. In the beginning they were all very tight micro coils. Lower ohm ratings didn't work nearly as well as higher ohms in the 2.2 to 2.8 range with 2.5 being the sweet spot. After a lot of forum research I decided to try some coils with space between winding. The final result is a 1.1 ohm coil consisting of ~4 loops of 30 gauge Kanthal with about a 2mm gap between loops. Amazing and very consistent. Huge clouds of vapor with zero harshness. Take a look at the Evic settings.