With the Ego C just remember that low ohm cartomizers usually use low voltage and high ohm cartomizers need high voltage
Low = 1.5ohm to 2.2ohm (3.4v up to 4.2v)
High = 2.4ohm to 3.0ohm (4.4v up to 6v)
This is just a general idea between what what ohms you might have and a voltage range you could use
With the K100 awesome
mod by the way I have one too
its a standard voltage of 3.7 and I would personally only run low ohm cartos to achieve the best
vape